pyklip package

Subpackages

Submodules

pyklip.covars module

pyklip.covars.delta(x, y, sigmas, *args)[source]

Generates a diagonal covariance matrix

C_ij = sigma_i sigma_j delta_{ij}

Parameters:
  • x (np.array) – 1-D array of x coordinates

  • y (np.array) – 1-D array of y coordinates

  • sigmas (np.array) – 1-D array of errors on each pixel

pyklip.covars.matern32(x, y, sigmas, corr_len)[source]

Generates a Matern (nu=3/2) covariance matrix that assumes x/y has the same correlation length

C_ij = sigma_i sigma_j (1 + sqrt(3) r_ij / l) exp(-sqrt(3) r_ij / l)

Parameters:
  • x (np.array) – 1-D array of x coordinates

  • y (np.array) – 1-D array of y coordinates

  • sigmas (np.array) – 1-D array of errors on each pixel

  • corr_len (float) – correlation length of the Matern function

Returns:

2-D covariance matrix parameterized by the Matern function

Return type:

cov (np.array)

pyklip.covars.sq_exp(x, y, sigmas, corr_len)[source]

Generates square exponential covariance matrix that assumes x/y has the same correlation length

C_ij = sigma_i sigma_j exp(-r_ij^2/[2 l^2])

Parameters:
  • x (np.array) – 1-D array of x coordinates

  • y (np.array) – 1-D array of y coordinates

  • sigmas (np.array) – 1-D array of errors on each pixel

  • corr_len (float) – correlation length (i.e. standard deviation of Gaussian)

  • mode (string) – either “numpy”, “cython”, or None, specifying the implementation of the kernel.

Returns:

2-D covariance matrix parameterized by the Matern function

Return type:

cov (np.array)

pyklip.empca module

pyklip.empca.np_calc_chisq(data, b, w, coef)[source]

Calculate chi squared

Parameters:
  • im – nim x npix, single-precision numpy.ndarray. Data to be fit by the basis images

  • b – nvec x npts, double precision numpy.ndarray. The nvec basis images.

  • w – nim x npts, single-precision numpy.ndarray. Weights (inverse variances) of the data.

  • coef – nvec x npts, double precision numpy.ndarray. The coefficients of the basis image fits.

Returns:

chisq, the total chi squared summed over all points and all images

pyklip.empca.set_pixel_weights(imflat, rflat, ivar=None, mode='standard', inner_sup=17, outer_sup=66)[source]
Parameters:
  • imflat – array of flattend images, shape (N, number of section indices)

  • rflat – radial component of the polar coordinates flattened to 1D, length = number of section indices

  • mode

    ‘standard’: assume poission statistics to calculate variance as sqrt(photon count)

    use inverse sqrt(variance) as pixel weights and multiply by a radial weighting

  • inner_sup – radius within which to supress weights

  • outer_sup – radius beyond which to supress weights

Returns:

pixel weights for empca

pyklip.empca.weighted_empca(data, weights=None, niter=25, nvec=5, randseed=1, maxcpus=1, silent=True)[source]

Perform iterative low-rank matrix approximation of data using weights.

Generated model vectors are not orthonormal and are not rotated/ranked by ability to model the data, but as a set they are good at describing the data.

Parameters:
  • data – images to model

  • weights – weights for every pixel

  • niter – maximum number of iterations to perform

  • nvec – number of vectors to solve (rank of the approximation)

  • randseed – rand num generator seed; if None, don’t re-initialize

  • maxcpus – maximum cpus to use for parallel programming

  • silent – bool, whether to show chi_squared for each iteration

Returns:

returns the best low-rank approximation to the data in a weighted least-squares sense (dot product of coefficients and basis vectors).

pyklip.fakes module

pyklip.fakes.LSQ_gauss2d(planet_image, x_grid, y_grid, a, x_cen, y_cen, sig)[source]

Calculate the squared norm of the residuals of the model with the data. Helper function for least square fit. The model is a 2d symmetric gaussian.

Parameters:
  • planet_image – stamp image (y,x) of the satellite spot.

  • x_grid – x samples grid as given by meshgrid.

  • y_grid – y samples grid as given by meshgrid.

  • a – amplitude of the 2d gaussian

  • x_cen – x center of the gaussian

  • y_cen – y center of the gaussian

  • sig – standard deviation of the gaussian

Returns:

Squared norm of the residuals

pyklip.fakes.PSFcubefit(frame, xguess, yguess, searchrad=10, psfs_func_list=None, wave_index=None, residuals=False, rmbackground=True, add_background2residual=False)[source]

Estimate satellite spot amplitude (peak value) by fitting a symmetric 2d gaussian. Fit parameters: x,y position, amplitude, standard deviation (same in x and y direction)

Parameters:
  • frame – the data - Array of size (y,x)

  • xguess – x location to fit the 2d guassian to.

  • yguess – y location to fit the 2d guassian to.

  • searchrad – 1/2 the length of the box used for the fit

  • psfs_func_list – List of spline fit function for the PSF_cube.

  • wave_index – Index of the current wavelength. In [0,36] for GPI. Only used when psfs_func_list is not None.

  • residuals – If True (Default = False) then calculate the residuals of the sat spot fit (gaussian or PSF cube).

  • rmbackground – If true (default), remove any background slope to the data stamp.

  • add_background2residual – If True (default is false) and if rmbackground was true, it adds the background that was removed to the returned residuals.

Returns:

scalar, Estimation of the peak flux of the satellite spot.

ie Amplitude of the fitted gaussian.

Return type:

returned_flux

pyklip.fakes.airyfit2d(frame, xguess, yguess, searchrad=5, guessfwhm=3, guesspeak=1)[source]

Fits a 2d airy function to the data at point (xguess, yguess)

Parameters:
  • frame – the data - Array of size (y,x)

  • xguess – location to fit the 2d guassian to (should be pretty accurate)

  • yguess – location to fit the 2d guassian to (should be pretty accurate)

  • searchrad – 1/2 the length of the box used for the fit

  • guessfwhm – approximate fwhm to fit to

Returns:

the peakflux of the Airy function fwhm: diameter between the first minima along one axis xfit: x position yfit: y position

Return type:

peakflux

pyklip.fakes.convert_pa_to_image_polar(pa, astr_hdr)[source]

Given a position angle (angle to North through East), calculate what polar angle theta (angle from +X CCW towards +Y) it corresponds to

Parameters:
  • pa – position angle in degrees

  • astr_hdr – wcs astrometry header (astropy.wcs)

Returns:

polar angle in degrees

Return type:

theta

pyklip.fakes.convert_polar_to_image_pa(theta, astr_hdr)[source]

Reversed engineer from covert_pa_to_image_polar by JB. Actually JB doesn’t quite understand how it works…

Parameters:
  • theta – parallactic angle in degrees

  • astr_hdr – wcs astrometry header (astropy.wcs)

Returns:

polar angle in degrees

Return type:

theta

pyklip.fakes.gauss2d(x0, y0, peak, sigma)[source]

2d symmetric guassian function for guassfit2d

Parameters:
  • x0 – center of gaussian

  • y0 – center of gaussian

  • peak – peak amplitude of guassian

  • sigma – stddev in both x and y directions

pyklip.fakes.gaussfit2d(frame, xguess, yguess, searchrad=5, guessfwhm=3, guesspeak=1, refinefit=True)[source]

Fits a 2d gaussian to the data at point (xguess, yguess)

Parameters:
  • frame – the data - Array of size (y,x)

  • xguess – location to fit the 2d guassian to (should be pretty accurate)

  • yguess – location to fit the 2d guassian to (should be pretty accurate)

  • searchrad – 1/2 the length of the box used for the fit

  • guessfwhm – approximate fwhm to fit to

  • guesspeak – approximate flux

  • refinefit – whether to refine the fit of the position of the guess

Returns:

the peakflux of the gaussian fwhm: fwhm of the PFS in pixels xfit: x position (only chagned if refinefit is True) yfit: y position (only chagned if refinefit is True)

Return type:

peakflux

pyklip.fakes.gaussfit2dLSQ(frame, xguess, yguess, searchrad=5, fit_centroid=False, residuals=False)[source]

Estimate satellite spot amplitude (peak value) by fitting a symmetric 2d gaussian. Fit parameters: x,y position, amplitude, standard deviation (same in x and y direction)

Parameters:
  • frame – the data - Array of size (y,x)

  • xguess – x location to fit the 2d guassian to.

  • yguess – y location to fit the 2d guassian to.

  • searchrad – 1/2 the length of the box used for the fit

  • fit_centroid – If False (default), disable the centroid fit and only fit the amplitude and the standard deviation

  • residuals – If True (Default = False) then calculate the residuals of the sat spot fit (gaussian or PSF cube).

Returns:

scalar, estimation of the peak flux of the satellite spot.

ie Amplitude of the fitted gaussian.

Return type:

returned_flux

pyklip.fakes.generate_dataset_with_fakes(dataset, fake_position_dict, fake_flux_dict, spectrum=None, PSF_cube=None, PSF_cube_wvs=None, star_type=None, mute=False, SpT_file_csv=None, real_planets_pos=None, sep_skip_real_pl=None, pa_skip_real_pl=None, dn_per_contrast=None, star_spec=None)[source]

Generate spectral datacubes with fake planets. It will do a copy of the cubes read in GPIData after having injected fake planets in them. This new set of cubes can then be reduced in the same manner as the campaign data.

Doesn’t work with remove slice: assumes that the dataset is made of a list of similar datacubes or images.

Parameters:
  • dataset – An object of type GPIData. The fakes are injected directly into dataset so you should make a copy of dataset prior to running this function. In order for the function to query simbad for the spectral type of the star, the attribute object_name needs to be defined in dataset.

  • fake_position_dict

    Dictionary defining the way the fake planets are positionned
    • fake_position_dict[“mode”]=”sector”: Put a planet in each klip sector. Can actually generate several

      datasets in which the planets will be shifted in separation and position angle with respect to one another. It can be usefull for fake based contrast curve calculation. Several parameters needs to be defined. - fake_position_dict[“annuli”]: Number of annulis in the image - fake_position_dict[“subsections”]: Number of angular sections in the image - fake_position_dict[“sep_shift”]: separation shift from the center of the sectors - fake_position_dict[“pa_shift”]: position angle shift from the center of the sectors

    • fake_position_dict[“mode”]=”custom”: Put planets at given (separation, position angle).

      The following parameter needs to be defined - fake_position_dict[“pa_sep_list”]: List of tuple [(r1,pa1),(r2,pa2),…] with each tuple giving

      the separation and position angle of each planet to be injected.

    • fake_position_dict[“mode”]=”ROC”: Generate fake for ROC curves calculation. Use hard-coded parameters.

    fake_flux_dict:

    Dictionary defining the way in which the flux of the fake is defined. - fake_flux_dict[“mode”]=”contrast”: Defines the contrast value of the fakes.

    • fake_flux_dict[“contrast”]: Contrast of the fake planets

    • fake_flux_dict[“mode”]=”SNR”: Defines the brightness of the fakes relatively to the satellite spots.
      • fake_flux_dict[“SNR”]: SNR wished for the fake planets.

      • fake_flux_dict[“sep_arr”]: Separation sampling of the contrast curve in pixels.

      • fake_flux_dict[“contrast_arr”]: 5 sigma contrast curve (planet to star ratio).

  • PSF_cube – the psf of the image. A numpy array with shape (wv, y, x)

  • PSF_cube_wvs – the wavelegnths that correspond to the input psfs

  • spectrum

    spectrum name (string) or array - “host_star_spec”: The spectrum from the star or the satellite spots is directly used.

    It is derived from the inverse of the calibrate_output() output.

    • ”constant”: Use a constant spectrum np.ones(nl).

    • other strings: name of the spectrum file in #pykliproot#/spectra/*/ with pykliproot the

      directory in which pyklip is installed. It that case it should be a spectrum from Mark Marley or one following the same convention. Spectrum will be corrected for transmission.

    • ndarray: 1D array with a user defined spectrum. Spectrum will be corrected for transmission.

  • star_type – Spectral type of the current star. If None, Simbad is queried.

  • mute – If True prevent printed log outputs.

  • suffix – Suffix to be added at the end of the filenames.

  • SpT_file_csv – Filename of the table (.csv) contaning the spectral type of the stars.

  • real_planets_pos – list of position of real point sources in the dataset that should be avoided when injecting fakes. [(sep1,pa1),(sep2,pa2),…] with the separation in pixels and the position angle in degrees.

  • sep_skip_real_pl – Limit in seperation of how close a fake can be injected of a known GOI.

  • pa_skip_real_pl – Limit in position angle of how close a fake can be injected of a known GOI.

  • dn_per_contrast – array of the same size as spectrum giving the conversion between the peak flux of a planet in data number and its contrast.

  • star_spec – 1D array stellar spectrum sampling dataset.wvs. Otherwise uses a pickles spectrum in which the temperature in interpolated from the spectral type.

pyklip.fakes.inject_disk(frames, centers, inputfluxes, astr_hdrs, pa, fwhm=3.5)[source]

Injects a fake disk into a dataset

Parameters:
  • frames – array of (N,y,x) for N is the total number of frames

  • centers – array of size (N,2) of [x,y] coordiantes of the image center

  • intputfluxes

    array of size N of the peak flux of the fake disk in each frame OR array of 2-D models (North up East left) to inject into the data.

    (Disk is assumed to be centered at center of image)

  • astr_hdrs – array of size N of the WCS headers

  • pa – position angles angle (in degrees) of disk plane

  • fwhm – if injecting a Gaussian disk (i.e inputfluxes is an array of floats), fwhm of Gaussian

Returns:

saves result in input “frames” variable

pyklip.fakes.inject_planet(frames, centers, inputflux, astr_hdrs, radius, pa, fwhm=3.5, thetas=None, stampsize=None, field_dependent_correction=None)[source]

Injects a fake planet into a dataset either using a Gaussian PSF or an input PSF

Parameters:
  • frames – array of (N,y,x) for N is the total number of frames

  • centers – array of size (N,2) of [x,y] coordiantes of the image center

  • inputflux – EITHER array of size N of the peak flux of the fake planet in each frame (will inject a Gaussian PSF) OR array of size (N,psfy,psfx) of template PSFs. The brightnesses should be scaled and the PSFs should be centered at the center of each of the template images

  • astr_hdrs – array of size N of the WCS headers

  • radius – separation of the planet from the star

  • pa – position angle (in degrees) of planet

  • fwhm – fwhm (in pixels) of gaussian

  • thetas – ignore PA, supply own thetas (CCW angle from +x axis toward +y) array of size N

  • stampsize – in pixels, the width of the square stamp to inject the image into. Defaults to 3*fwhm if None

  • field_dependent_correction – a function of the form ``output_stamp = correction(input_stamp, input_dx, input_dy) where, input_stamp is a 2-D image of shape (y_stamp, x_stamp). input_dx and input_dy have the same shape and represent the offset of each pixel from the star (in pixel units). The function returns an output_stamp of the same shape, but corrected for any field dependent throughputs or distortions.

Returns:

saves result in input “frames” variable

pyklip.fakes.retrieve_planet(frames, centers, astr_hdrs, sep, pa, searchrad=7, guessfwhm=3.0, guesspeak=1, refinefit=True, thetas=None)[source]

Retrives the planet properties from a series of frames given a separation and PA

Parameters:
  • frames – frames of data to retrieve planet. Can be a single 2-D image ([y,x]) for a series/cube ([N,y,x])

  • centers – coordiantes of the image center. Can be [2]-element lst or an array that matches array of frames [N,2]

  • astr_hdrs – astr_hdrs, can be a single one or an array of N of them

  • sep – radial distance in pixels

  • PA – parallactic angle in degrees

  • searchrad – 1/2 the length of the box used for the fit

  • guessfwhm – approximate fwhm to fit to

  • guesspeak – approximate flux

  • refinefit – whether or not to refine the positioning of the planet

  • thetas – ignore PA, supply own thetas (CCW angle from +x axis toward +y) single number or array of size N

Returns:

(peakflux, x, y, fwhm). A single tuple if one frame passed in. Otherwise an array of tuples

Return type:

measured

pyklip.fakes.retrieve_planet_flux(frames, centers, astr_hdrs, sep, pa, searchrad=7, guessfwhm=3.0, guesspeak=1, refinefit=False, thetas=None)[source]

Retrives the planet flux from a series of frames given a separation and PA

Parameters:
  • frames – frames of data to retrieve planet. Can be a single 2-D image ([y,x]) for a series/cube ([N,y,x])

  • centers – coordiantes of the image center. Can be [2]-element lst or an array that matches array of frames [N,2]

  • astr_hdrs – astr_hdrs, can be a single one or an array of N of them

  • sep – radial distance in pixels

  • PA – parallactic angle in degrees

  • searchrad – 1/2 the length of the box used for the fit

  • guessfwhm – approximate fwhm to fit to

  • guesspeak – approximate flux

  • refinefit – whether or not to refine the positioning of the planet

  • thetas – ignore PA, supply own thetas (CCW angle from +x axis toward +y) single number or array of size N

Returns:

either a single peak flux or an array depending on whether a single frame or multiple frames

where passed in

Return type:

peakflux

pyklip.fitpsf module

class pyklip.fitpsf.FMAstrometry(guess_sep, guess_pa, fitboxsize, method='mcmc')[source]

Bases: FitPSF

Specifically for fitting astrometry of a directly imaged companion relative to its star. Extension of pyklip.fitpsf.FitPSF.

Parameters:
  • guess_sep – the guessed separation (pixels)

  • guess_pa – the guessed position angle (degrees)

  • fitboxsize – fitting box side length (pixels)

  • method (str) – either ‘mcmc’ or ‘maxl’ depending on framework you want. Defaults to ‘mcmc’.

guess_sep

(initialization) guess separation for planet [pixels]

Type:

float

guess_pa

(initialization) guess PA for planet [degrees]

Type:

float

guess_RA_offset

(initialization) guess RA offset [pixels]

Type:

float

guess_Dec_offset

(initialization) guess Dec offset [pixels]

Type:

float

raw_RA_offset

(result) the raw result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

raw_Dec_offset

(result) the raw result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

raw_flux

(result) factor to scale the FM to match the flux of the data

Type:

pyklip.fitpsf.ParamRange

covar_params

(result) hyperparameters for the Gaussian process

Type:

list of pyklip.fitpsf.ParamRange

raw_sep

(result) the inferred raw result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

raw_PA

(result) the inferred raw result from the MCMC fit for the planet’s location [degrees]

Type:

pyklip.fitpsf.ParamRange

RA_offset

(result) the RA offset of the planet that includes all astrometric errors [pixels or mas]

Type:

pyklip.fitpsf.ParamRange

Dec_offset

(result) the Dec offset of the planet that includes all astrometric errors [pixels or mas]

Type:

pyklip.fitpsf.ParamRange

sep

(result) the separation of the planet that includes all astrometric errors [pixels or mas]

Type:

pyklip.fitpsf.ParamRange

PA

(result) the PA of the planet that includes all astrometric errors [degrees]

Type:

pyklip.fitpsf.ParamRange

fm_stamp

(fitting) The 2-D stamp of the forward model (centered at the nearest pixel to the guessed location)

Type:

np.array

data_stamp

(fitting) The 2-D stamp of the data (centered at the nearest pixel to the guessed location)

Type:

np.array

noise_map

(fitting) The 2-D stamp of the noise for each pixel the data computed assuming azimuthally similar noise

Type:

np.array

padding

amount of pixels on one side to pad the data/forward model stamp

Type:

int

sampler

an instance of the emcee EnsambleSampler. Only for Bayesian fit. See emcee docs for more details.

Type:

emcee.EnsembleSampler

fit_astrometry(nwalkers=100, nburn=200, nsteps=800, save_chain=True, chain_output='bka-chain.pkl', numthreads=None)[source]

Fits the PSF of the planet in either a frequentist or Bayesian way depending on initialization.

Parameters:
  • nwalkers – number of walkers (mcmc-only)

  • nburn – numbe of samples of burn-in for each walker (mcmc-only)

  • nsteps – number of samples each walker takes (mcmc-only)

  • save_chain – if True, save the output in a pickled file (mcmc-only)

  • chain_output – filename to output the chain to (mcmc-only)

  • numthreads – number of threads to use (mcmc-only)

Returns:

generate_data_stamp(data, data_center, data_wcs=None, noise_map=None, dr=4, exclusion_radius=10)[source]

Generate a stamp of the data_stamp ~centered on planet and also corresponding noise map

Parameters:
  • data – the final collapsed data_stamp (2-D)

  • data_center – location of star in the data_stamp.

  • data_wcs – sky angles WCS object. To rotate the image properly [NOT YET IMPLMETNED] if None, data_stamp is already rotated North up East left

  • noise_map – if not None, noise map for each pixel in the data_stamp (2-D). if None, one will be generated assuming azimuthal noise using an annulus widthh of dr

  • dr – width of annulus in pixels from which the noise map will be generated

  • exclusion_radius – radius around the guess planet location which doens’t get factored into noise estimate

Returns:

generate_fm_stamp(fm_image, fm_center, fm_wcs=None, extract=True, padding=5)[source]

Generates a stamp of the forward model and stores it in self.fm_stamp :param fm_image: full imgae containing the fm_stamp :param fm_center: [x,y] center of image (assuing fm_stamp is located at sep/PA) corresponding to guess_sep and guess_pa :param fm_wcs: if not None, specifies the sky angles in the image. If None, assume image is North up East left :param extract: if True, need to extract the forward model from the image. Otherwise, assume the fm_stamp is already

centered in the frame (fm_image.shape // 2)

Parameters:

padding – number of pixels on each side in addition to the fitboxsize to extract to pad the fm_stamp (should be >= 1)

Returns:

propogate_errs(star_center_err=None, platescale=None, platescale_err=None, pa_offset=None, pa_uncertainty=None)[source]

Propogate astrometric error. Stores results in its own fields

Parameters:
  • star_center_err (float) – uncertainity of the star location (pixels)

  • platescale (float) – mas/pix conversion to angular coordinates

  • platescale_err (float) – mas/pix error on the platescale

  • pa_offset (float) – Offset, in the same direction as position angle, to set North up (degrees)

  • pa_uncertainity (float) – Error on position angle/true North calibration (Degrees)

class pyklip.fitpsf.FitPSF(fitboxsize, method='mcmc')[source]

Bases: object

Base class to perform astrometry on direct imaging data_stamp using GP regression. Can utilize a Bayesian framework with MCMC or a frequentist framework with least squares.

Parameters:
  • fitboxsize – fitting box side length (pixels)

  • method (str) – either ‘mcmc’ or ‘maxl’ depending on framework you want. Defaults to ‘mcmc’.

  • fmt (str) – either ‘seppa’ or ‘xy’ depending on how you want to input the guess coordiantes

guess_x

(initialization) guess x position [pixels]

Type:

float

guess_y

(initialization) guess y positon [pixels]

Type:

float

guess_flux

guess scale factor between model and data

Type:

float

fit_x

(result) the result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

fit_y

(result) the result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

fit_flux

(result) factor to scale the FM to match the flux of the data

Type:

pyklip.fitpsf.ParamRange

covar_params

(result) hyperparameters for the Gaussian processa

Type:

list of pyklip.fitpsf.ParamRange

fm_stamp

(fitting) The 2-D stamp of the forward model (centered at the nearest pixel to the guessed location)

Type:

np.array

data_stamp

(fitting) The stamp of the data (centered at the nearest pixel to the guessed location) (2-D unless there were NaNs in which 1-D)

Type:

np.array

noise_map

(fitting) The stamp of the noise for each pixel the data computed assuming azimuthally similar noise (same dim as data_stamp)

Type:

np.array

padding

amount of pixels on one side to pad the data/forward model stamp

Type:

int

sampler

an instance of the emcee EnsambleSampler. Only for Bayesian fit. See emcee docs for more details.

Type:

emcee.EnsembleSampler

best_fit_and_residuals(fig=None)[source]

Generate a plot of the best fit FM compared with the data_stamp and also the residuals :param fig: if not None, a matplotlib Figure object :type fig: matplotlib.Figure

Returns:

the Figure object. If input fig is None, function will make a new one

Return type:

fig (matplotlib.Figure)

fit_psf(nwalkers=100, nburn=200, nsteps=800, save_chain=True, chain_output='bka-chain.pkl', numthreads=None)[source]

Fits the PSF to the data in either a frequentist or Bayesian way depending on initialization.

Parameters:
  • nwalkers – number of walkers (mcmc-only)

  • nburn – numbe of samples of burn-in for each walker (mcmc-only)

  • nsteps – number of samples each walker takes (mcmc-only)

  • save_chain – if True, save the output in a pickled file (mcmc-only)

  • chain_output – filename to output the chain to (mcmc-only)

  • numthreads – number of threads to use (mcmc-only)

Returns:

generate_data_stamp(data, guess_loc, noise_map, radial_noise_center=None, dr=4, exclusion_radius=10)[source]

Generate a stamp of the data_stamp ~centered on planet and also corresponding noise map :param data: the final collapsed data_stamp (2-D) :param guess_loc: guess location of where to fit the model in the data :param noise_map: if not None, noise map for each pixel (either same shape as input data, or shape of data stamp)

if None, one will be generated assuming azimuthal noise using an annulus widthh of dr. radial_noise_center MUST be defined.

Parameters:
  • radial_noise_center – if we assume the noise is azimuthally symmetric and changes radially, this is the [x,y] center for it

  • dr – width of annulus in pixels from which the noise map will be generated

  • exclusion_radius – radius around the guess planet location which doens’t get factored into the radial noise estimate

Returns:

generate_fm_stamp(fm_image, fm_pos=None, fm_wcs=None, extract=True, padding=5)[source]

Generates a stamp of the forward model and stores it in self.fm_stamp :param fm_image: full image containing the fm_stamp :param fm_pos: [x,y] location of the forwrd model in the fm_image :param fm_wcs: if not None, specifies the sky angles in the image. If None, assume image is North up East left :param extract: if True, need to extract the forward model from the image. Otherwise, assume the fm_stamp is already

centered in the frame (fm_image.shape // 2)

Parameters:

padding – number of pixels on each side in addition to the fitboxsize to extract to pad the fm_stamp (should be >= 1)

Returns:

property guess_flux
make_corner_plot(fig=None)[source]

Generate a corner plot of the posteriors from the MCMC :param fig: if not None, a matplotlib Figure object

Returns:

the Figure object. If input fig is None, function will make a new one

Return type:

fig

set_bounds(dx, dy, df, covar_param_bounds, read_noise_bounds=None)[source]

Set bounds on Bayesian priors. All paramters can be a 2 element tuple/list/array that specifies the lower and upper bounds x_min < x < x_max. Or a single value whose interpretation is specified below If you are passing in both lower and upper bounds, both should be in linear scale! :param dx: Distance from initial guess position in pixels. For a single value, this specifies the largest distance

form the initial guess (i.e. x_guess - dx < x < x_guess + dx)

Parameters:
  • dy – Same as dx except with y

  • df – Flux range. If single value, specifies how many orders of 10 the flux factor can span in one direction (i.e. log_10(guess_flux) - df < log_10(guess_flux) < log_10(guess_flux) + df

  • covar_param_bounds – Params for covariance matrix. Like df, single value specifies how many orders of magnitude parameter can span. Otherwise, should be a list of 2-elem touples

  • read_noise_bounds – Param for read noise term. If single value, specifies how close to 0 it can go based on powers of 10 (i.e. log_10(-read_noise_bound) < read_noise < 1 )

Returns:

set_kernel(covar, covar_param_guesses, covar_param_labels, include_readnoise=False, read_noise_fraction=0.01)[source]

Set the Gaussian process kernel used in our fit

Parameters:
  • covar – Covariance kernel for GP regression. If string, can be “matern32” or “sqexp” or “diag” Can also be a function: cov = cov_function(x_indices, y_indices, sigmas, cov_params)

  • covar_param_guesses – a list of guesses on the hyperparmeteres (size of N_hyperparams). This can be an empty list for ‘diag’.

  • covar_param_labels – a list of strings labelling each covariance parameter

  • include_readnoise – if True, part of the noise is a purely diagonal term (i.e. read/photon noise)

  • read_noise_fraction – fraction of the total measured noise is read noise (between 0 and 1)

Returns:

class pyklip.fitpsf.ParamRange(bestfit, err_range)[source]

Bases: object

Stores the best fit value and uncertainities for a parameter in a neat fasion

Parameters:
  • bestfit (float) – the bestfit value

  • err_range – either a float or a 2-element tuple (+val1, -val2) and gives the 1-sigma range

bestfit

the bestfit value

Type:

float

error

the average 1-sigma error

Type:

float

error_2sided

[+error1, -error2] 2-element array with asymmetric errors

Type:

np.array

class pyklip.fitpsf.PlanetEvidence(guess_sep, guess_pa, fitboxsize, sampling_outputdir, l_only=False, fm_basename='Planet', null_basename='Null')[source]

Bases: FMAstrometry

Specifically for nested sampling of the parameter space of a directly imaged companion relative to its star. Extension of pyklip.fitpsf.FitPSF.

Parameters:
  • guess_sep – the guessed separation (pixels)

  • guess_pa – the guessed position angle (degrees)

  • fitboxsize – fitting box side length (pixels)

  • fm_basename – Prefix of the foward model sampling files multinest saves in /chains/

  • null_basename – Prefix of the null hypothesis model sampling files multinest saves in /chains/

guess_sep

(initialization) guess separation for planet [pixels]

Type:

float

guess_pa

(initialization) guess PA for planet [degrees]

Type:

float

guess_RA_offset

(initialization) guess RA offset [pixels]

Type:

float

guess_Dec_offset

(initialization) guess Dec offset [pixels]

Type:

float

raw_RA_offset

(result) the raw result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

raw_Dec_offset

(result) the raw result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

raw_flux

(result) factor to scale the FM to match the flux of the data

Type:

pyklip.fitpsf.ParamRange

covar_params

(result) hyperparameters for the Gaussian process

Type:

list of pyklip.fitpsf.ParamRange

raw_sep

(result) the inferred raw result from the MCMC fit for the planet’s location [pixels]

Type:

pyklip.fitpsf.ParamRange

raw_PA

(result) the inferred raw result from the MCMC fit for the planet’s location [degrees]

Type:

pyklip.fitpsf.ParamRange

RA_offset

(result) the RA offset of the planet that includes all astrometric errors [pixels or mas]

Type:

pyklip.fitpsf.ParamRange

Dec_offset

(result) the Dec offset of the planet that includes all astrometric errors [pixels or mas]

Type:

pyklip.fitpsf.ParamRange

sep

(result) the separation of the planet that includes all astrometric errors [pixels or mas]

Type:

pyklip.fitpsf.ParamRange

PA

(result) the PA of the planet that includes all astrometric errors [degrees]

Type:

pyklip.fitpsf.ParamRange

fm_stamp

(fitting) The 2-D stamp of the forward model (centered at the nearest pixel to the guessed location)

Type:

np.array

data_stamp

(fitting) The 2-D stamp of the data (centered at the nearest pixel to the guessed location)

Type:

np.array

noise_map

(fitting) The 2-D stamp of the noise for each pixel the data computed assuming azimuthally similar noise

Type:

np.array

padding

amount of pixels on one side to pad the data/forward model stamp

Type:

int

sampler

function that runs the pymultinest sampling for both hypotheses

Type:

pymultinest.run

fit_plots()[source]
fit_stats()[source]
fm_residuals()[source]
multifit()[source]

Nested sampling parameter estimation and evidence calculation for the forward model and correlated noise.

nested_corner_plots(posts, n_dim)[source]
pyklip.fitpsf.lnlike(fitparams, fma, cov_func, readnoise=False, negate=False)[source]

Likelihood function :param fitparams: array of params (size N). First three are [dRA,dDec,f]. Additional parameters are GP hyperparams

dRA,dDec: RA,Dec offsets from star. Also coordianaes in self.data_{RA,Dec}_offset f: flux scale factor to normalizae the flux of the data_stamp to the model

Parameters:
  • fma (FMAstrometry) – a FMAstrometry object that has been fully set up to run

  • cov_func (function) – function that given an input [x,y] coordinate array returns the covariance matrix e.g. cov = cov_function(x_indices, y_indices, sigmas, cov_params)

  • readnoise (bool) – If True, the last fitparam fits for diagonal noise

  • negate (bool) – if True, negatives the probability (used for minimization algos)

Returns:

log of likelihood function (minus a constant factor)

Return type:

likeli

pyklip.fitpsf.lnprior(fitparams, bounds, readnoise=False, negate=False)[source]

Bayesian prior

Parameters:
  • fitparams – array of params (size N)

  • bounds – array of (N,2) with corresponding lower and upper bound of params bounds[i,0] <= fitparams[i] < bounds[i,1]

  • readnoise (bool) – If True, the last fitparam fits for diagonal noise

  • negate (bool) – if True, negatives the probability (used for minimization algos)

Returns:

0 if inside bound ranges, -inf if outside

Return type:

prior

pyklip.fitpsf.lnprob(fitparams, fma, bounds, cov_func, readnoise=False, negate=False)[source]

Function to compute the relative posterior probabiltiy. Product of likelihood and prior :param fitparams: array of params (size N). First three are [dRA,dDec,f]. Additional parameters are GP hyperparams

dRA,dDec: RA,Dec offsets from star. Also coordianaes in self.data_{RA,Dec}_offset f: flux scale factor to normalizae the flux of the data_stamp to the model

Parameters:
  • fma – a FMAstrometry object that has been fully set up to run

  • bounds – array of (N,2) with corresponding lower and upper bound of params bounds[i,0] <= fitparams[i] < bounds[i,1]

  • cov_func – function that given an input [x,y] coordinate array returns the covariance matrix e.g. cov = cov_function(x_indices, y_indices, sigmas, cov_params)

  • readnoise (bool) – If True, the last fitparam fits for diagonal noise

  • negate (bool) – if True, negatives the probability (used for minimization algos)

Returns:

pyklip.fitpsf.quick_psf_fit(data, psf, x_guess, y_guess, fitboxsize)[source]

A wrapper for a quick maximum likelihood fit to a PSF to the data.

Parameters:
  • data (np.array) – 2-D data frame

  • psf (np.array) – 2-D PSF template. This should be smaller than the size of data and larger than the fitboxsize

  • x_guess (float) – approximate x position of the location you are fitting the psf to

  • y_guess (float) – approximate y position of the location you are fitting the psf to

  • fitboxsize (int) – fitting region is a square. This is the lenght of one side of the square

Returns:

x_fit, y_fit, flux_fit x_fit (float): x position y_fit (float): y position flux_fit (float): multiplicative scale factor for the psf to match the data

pyklip.fm module

pyklip.fm.calculate_fm(delta_KL_nospec, original_KL, numbasis, sci, model_sci, inputflux=None)[source]

Calculate what the PSF looks up post-KLIP using knowledge of the input PSF, assumed spectrum of the science target, and the partially calculated KL modes (Delta Z_k^lambda in Laurent’s paper). If inputflux is None, the spectral dependence has already been folded into delta_KL_nospec (treat it as delta_KL).

Note: if inputflux is None and delta_KL_nospec has three dimensions (ie delta_KL_nospec was calculated using pertrurb_nospec() or perturb_nospec_modelsBased()) then only klipped_oversub and klipped_selfsub are returned. Besides they will have an extra first spectral dimension.

Parameters:
  • delta_KL_nospec – perturbed KL modes but without the spectral info. delta_KL = spectrum x delta_Kl_nospec. Shape is (numKL, wv, pix). If inputflux is None, delta_KL_nospec = delta_KL

  • orignal_KL – unpertrubed KL modes (array of size [numbasis, numpix])

  • numbasis – array of KL mode cutoffs If numbasis is [None] the number of KL modes to be used is automatically picked based on the eigenvalues.

  • sci – array of size p representing the science data

  • model_sci – array of size p corresponding to the PSF of the science frame

  • input_spectrum – array of size wv with the assumed spectrum of the model

If delta_KL_nospec does NOT include a spectral dimension or if inputflux is not None: :returns:

array of shape (b,p) showing the forward modelled PSF

Skipped if inputflux = None, and delta_KL_nospec has 3 dimensions.

klipped_oversub: array of shape (b, p) showing the effect of oversubtraction as a function of KL modes klipped_selfsub: array of shape (b, p) showing the effect of selfsubtraction as a function of KL modes Note: psf_FM = model_sci - klipped_oversub - klipped_selfsub to get the FM psf as a function of K Lmodes

(shape of b,p)

Return type:

fm_psf

If inputflux = None and if delta_KL_nospec include a spectral dimension: :returns: Sum(<S|KL>KL) with klipped_oversub.shape = (size(numbasis),Npix)

klipped_selfsub: Sum(<N|DKL>KL) + Sum(<N|KL>DKL) with klipped_selfsub.shape = (size(numbasis),N_lambda or N_ref,N_pix)

Return type:

klipped_oversub

pyklip.fm.calculate_fm_singleNumbasis(delta_KL_nospec, original_KL, numbasis, sci, model_sci, inputflux=None)[source]

Same function as calculate_fm() but faster when numbasis has only one element. It doesn’t do the mutliplication with the triangular matrix.

Calculate what the PSF looks up post-KLIP using knowledge of the input PSF, assumed spectrum of the science target, and the partially calculated KL modes (Delta Z_k^lambda in Laurent’s paper). If inputflux is None, the spectral dependence has already been folded into delta_KL_nospec (treat it as delta_KL).

Note: if inputflux is None and delta_KL_nospec has three dimensions (ie delta_KL_nospec was calculated using pertrurb_nospec() or perturb_nospec_modelsBased()) then only klipped_oversub and klipped_selfsub are returned. Besides they will have an extra first spectral dimension.

Parameters:
  • delta_KL_nospec – perturbed KL modes but without the spectral info. delta_KL = spectrum x delta_Kl_nospec. Shape is (numKL, wv, pix). If inputflux is None, delta_KL_nospec = delta_KL

  • orignal_KL – unpertrubed KL modes (array of size [numbasis, numpix])

  • numbasis – array of (ONE ELEMENT ONLY) KL mode cutoffs If numbasis is [None] the number of KL modes to be used is automatically picked based on the eigenvalues.

  • sci – array of size p representing the science data

  • model_sci – array of size p corresponding to the PSF of the science frame

  • input_spectrum – array of size wv with the assumed spectrum of the model

If delta_KL_nospec does NOT include a spectral dimension or if inputflux is not None: :returns:

array of shape (b,p) showing the forward modelled PSF

Skipped if inputflux = None, and delta_KL_nospec has 3 dimensions.

klipped_oversub: array of shape (b, p) showing the effect of oversubtraction as a function of KL modes klipped_selfsub: array of shape (b, p) showing the effect of selfsubtraction as a function of KL modes Note: psf_FM = model_sci - klipped_oversub - klipped_selfsub to get the FM psf as a function of K Lmodes

(shape of b,p)

Return type:

fm_psf

If inputflux = None and if delta_KL_nospec include a spectral dimension: :returns: Sum(<S|KL>KL) with klipped_oversub.shape = (size(numbasis),Npix)

klipped_selfsub: Sum(<N|DKL>KL) + Sum(<N|KL>DKL) with klipped_selfsub.shape = (size(numbasis),N_lambda or N_ref,N_pix)

Return type:

klipped_oversub

pyklip.fm.calculate_validity(covar_perturb, models_ref, numbasis, evals_orig, covar_orig, evecs_orig, KL_orig, delta_KL)[source]
Calculate the validity of the perturbation based on the eigenvalues or the 2nd order term compared

to the 0th order term of the covariance matrix expansion

Parameters:
  • evals_perturb – linear expansion of the perturbed covariance matrix (C_AS). Shape of N x N

  • models_ref – N x p array of the N models corresponding to reference images. Each model should contain spectral information

  • numbasis – array of KL mode cutoffs

  • evevs_orig – size of [N, maxKL]

Returns:

perturbed KL modes. Shape is (numKL, wv, pix)

Return type:

delta_KL_nospec

pyklip.fm.find_id_nearest(array, value)[source]

Find index of the closest value in input array to input value :param array: 1D array :param value: scalar value

Returns:

Index of the nearest value in array

pyklip.fm.klip_dataset(dataset, fm_class, mode='ADI+SDI', outputdir='.', fileprefix='pyklipfm', annuli=5, subsections=4, OWA=None, N_pix_sector=None, movement=None, flux_overlap=0.1, PSF_FWHM=3.5, minrot=0, padding=0, numbasis=None, maxnumbasis=None, numthreads=None, corr_smooth=1, calibrate_flux=False, aligned_center=None, psf_library=None, spectrum=None, highpass=False, annuli_spacing='constant', save_klipped=True, mute_progression=False, time_collapse='mean')[source]

Run KLIP-FM on a dataset object

Parameters:
  • dataset – an instance of Instrument.Data (see instruments/ subfolder)

  • fm_class – class that implements the the forward modelling functionality

  • mode – some combination of ADI, SDI, and RDI (e.g. “ADI+SDI”, “RDI”). Note that note all FM classes support RDI.

  • anuuli – Annuli to use for KLIP. Can be a number, or a list of 2-element tuples (a, b) specifying the pixel bondaries (a <= r < b) for each annulus

  • subsections – Sections to break each annuli into. Can be a number [integer], or a list of 2-element tuples (a, b) specifying the positon angle boundaries (a <= PA < b) for each section [radians]

  • OWA – if defined, the outer working angle for pyklip. Otherwise, it will pick it as the cloest distance to a nan in the first frame

  • N_pix_sector

    Rough number of pixels in a sector. Overwriting subsections and making it sepration dependent. The number of subsections is defined such that the number of pixel is just higher than N_pix_sector. I.e. subsections = floor(pi*(r_max^2-r_min^2)/N_pix_sector) Warning: There is a bug if N_pix_sector is too big for the first annulus. The annulus is defined from

    0 to 2pi which create a bug later on. It is probably in the way pa_start and pa_end are defined in fm_from_eigen(). (I am taking about matched filter by the way)

  • movement – minimum amount of movement (in pixels) of an astrophysical source to consider using that image for a refernece PSF

  • flux_overlap – Maximum fraction of flux overlap between a slice and any reference frames included in the covariance matrix. Flux_overlap should be used instead of “movement” when a template spectrum is used. However if movement is not None then the old code is used and flux_overlap is ignored. The overlap is estimated for 1D gaussians with FWHM defined by PSF_FWHM. So note that the overlap is not exactly the overlap of two real 2D PSF for a given instrument but it will behave similarly.

  • PSF_FWHM – FWHM of the PSF used to calculate the overlap (cf flux_overlap). Default is FWHM = 3.5 corresponding to sigma ~ 1.5.

  • minrot – minimum PA rotation (in degrees) to be considered for use as a reference PSF (good for disks)

  • padding – for each sector, how many extra pixels of padding should we have around the sides.

  • numbasis – number of KL basis vectors to use (can be a scalar or list like). Length of b If numbasis is [None] the number of KL modes to be used is automatically picked based on the eigenvalues.

  • maxnumbasis – Number of KL modes to be calculated from whcih numbasis modes will be taken.

  • corr_smooth (float) – size of sigma of Gaussian smoothing kernel (in pixels) when computing most correlated PSFs. If 0, no smoothing

  • numthreads – number of threads to use. If none, defaults to using all the cores of the cpu

  • calibrate_flux – if true, flux calibrates the regular KLIP subtracted data. DOES NOT CALIBRATE THE FM

  • aligned_center – array of 2 elements [x,y] that all the KLIP subtracted images will be centered on for image registration

  • psf_library – a rdi.PSFLibrary object with a PSF Library for RDI

  • spectrum

    (only applicable for SDI) if not None, optimizes the choice of the reference PSFs based on the

    spectrum shape.

    • an array: of length N with the flux of the template spectrum at each wavelength.

    • a string: Currently only supports “methane” between 1 and 10 microns.

    Uses minmove to determine the separation from the center of the segment to determine contamination and the size of the PSF (TODO: make PSF size another quantity) (e.g. minmove=3, checks how much contamination is within 3 pixels of the hypothetical source) if smaller than 10%, (hard coded quantity), then use it for reference PSF

  • highpass – if True, run a Gaussian high pass filter (default size is sigma=imgsize/10) can also be a number specifying FWHM of box in pixel units

  • annuli_spacing – how to distribute the annuli radially. Currently three options. Constant (equally spaced), log (logarithmical expansion with r), and linear (linearly expansion with r)

  • save_klipped – if True, will save the regular klipped image. If false, it wil not and sub_imgs will return None

  • mute_progression – Mute the printing of the progression percentage. Indeed sometimes the overwriting feature doesn’t work and one ends up with thousands of printed lines. Therefore muting it can be a good idea.

  • time_collapse – how to collapse the data in time. Currently support: “mean”, “weighted-mean”

pyklip.fm.klip_math(sci, refs, numbasis, covar_psfs=None, model_sci=None, models_ref=None, spec_included=False, spec_from_model=False)[source]

linear algebra of KLIP with linear perturbation disks and point source

Parameters:
  • sci – array of length p containing the science data

  • refs – N x p array of the N reference images that characterizes the extended source with p pixels

  • numbasis – number of KLIP basis vectors to use (can be an int or an array of ints of length b) If numbasis is [None] the number of KL modes to be used is automatically picked based on the eigenvalues.

  • covar_psfs – covariance matrix of reference images (for large N, useful). Normalized following numpy normalization in np.cov documentation

  • in (# The following arguments must all be passed) –

  • work (or none of them for klip_math to) –

  • models_ref – N x p array of the N models corresponding to reference images. Each model should be normalized to unity (no flux information)

  • model_sci – array of size p corresponding to the PSF of the science frame

  • Sel_wv – wv x N array of the the corresponding wavelength for each reference PSF

  • input_spectrum – array of size wv with the assumed spectrum of the model

Returns:

array of shape (p,b) that is the PSF subtracted data for each of the b KLIP basis

cutoffs. If numbasis was an int, then sub_img_row_selected is just an array of length p

KL_basis: array of KL basis (shape of [numbasis, p]) If models_ref is passed in (not None):

delta_KL_nospec: array of shape (b, wv, p) that is the almost perturbed KL modes just missing spectral info

Otherwise:

evals: array of eigenvalues (size of max number of KL basis requested aka nummaxKL) evecs: array of corresponding eigenvectors (shape of [p, nummaxKL])

Return type:

sub_img_rows_selected

pyklip.fm.klip_parallelized(imgs, centers, parangs, wvs, IWA, fm_class, OWA=None, mode='ADI+SDI', annuli=5, subsections=4, movement=None, flux_overlap=0.1, PSF_FWHM=3.5, numbasis=None, maxnumbasis=None, corr_smooth=1, aligned_center=None, numthreads=None, minrot=0, maxrot=360, spectrum=None, psf_library=None, psf_library_good=None, psf_library_corr=None, padding=0, save_klipped=True, flipx=True, N_pix_sector=None, mute_progression=False, annuli_spacing='constant', compute_noise_cube=False)[source]

multithreaded KLIP PSF Subtraction

Parameters:
  • imgs – array of 2D images for ADI. Shape of array (N,y,x)

  • centers – N by 2 array of (x,y) coordinates of image centers

  • parangs – N length array detailing parallactic angle of each image

  • wvs – N length array of the wavelengths

  • IWA – inner working angle (in pixels)

  • fm_class – class that implements the the forward modelling functionality

  • OWA – if defined, the outer working angle for pyklip. Otherwise, it will pick it as the cloest distance to a nan in the first frame

  • mode – one of [‘ADI’, ‘SDI’, ‘ADI+SDI’] for ADI, SDI, or ADI+SDI

  • anuuli – Annuli to use for KLIP. Can be a number, or a list of 2-element tuples (a, b) specifying the pixel bondaries (a <= r < b) for each annulus

  • subsections – Sections to break each annuli into. Can be a number [integer], or a list of 2-element tuples (a, b) specifying the positon angle boundaries (a <= PA < b) for each section [radians]

  • N_pix_sector

    Rough number of pixels in a sector. Overwriting subsections and making it sepration dependent. The number of subsections is defined such that the number of pixel is just higher than N_pix_sector. I.e. subsections = floor(pi*(r_max^2-r_min^2)/N_pix_sector) Warning: There is a bug if N_pix_sector is too big for the first annulus. The annulus is defined from

    0 to 2pi which create a bug later on. It is probably in the way pa_start and pa_end are defined in fm_from_eigen().

  • movement – minimum amount of movement (in pixels) of an astrophysical source to consider using that image for a refernece PSF

  • flux_overlap – Maximum fraction of flux overlap between a slice and any reference frames included in the covariance matrix. Flux_overlap should be used instead of “movement” when a template spectrum is used. However if movement is not None then the old code is used and flux_overlap is ignored. The overlap is estimated for 1D gaussians with FWHM defined by PSF_FWHM. So note that the overlap is not exactly the overlap of two real 2D PSF for a given instrument but it will behave similarly.

  • PSF_FWHM – FWHM of the PSF used to calculate the overlap (cf flux_overlap). Default is FWHM = 3.5 corresponding to sigma ~ 1.5.

  • numbasis – number of KL basis vectors to use (can be a scalar or list like). Length of b If numbasis is [None] the number of KL modes to be used is automatically picked based on the eigenvalues.

  • maxnumbasis – Number of KL modes to be calculated from whcih numbasis modes will be taken.

  • corr_smooth (float) – size of sigma of Gaussian smoothing kernel (in pixels) when computing most correlated PSFs. If 0, no smoothing

  • aligned_center – array of 2 elements [x,y] that all the KLIP subtracted images will be centered on for image registration

  • numthreads – number of threads to use. If none, defaults to using all the cores of the cpu

  • minrot – minimum PA rotation (in degrees) to be considered for use as a reference PSF (good for disks)

  • maxrot – maximum PA rotation (in degrees) to be considered for use as a reference PSF (temporal variability)

  • spectrum – if not None, a array of length N with the flux of the template spectrum at each wavelength. Uses minmove to determine the separation from the center of the segment to determine contamination and the size of the PSF (TODO: make PSF size another quanitity) (e.g. minmove=3, checks how much containmination is within 3 pixels of the hypothetical source) if smaller than 10%, (hard coded quantity), then use it for reference PSF

  • padding – for each sector, how many extra pixels of padding should we have around the sides.

  • save_klipped – if True, will save the regular klipped image. If false, it wil not and sub_imgs will return None

  • flipx – if True, flips x axis after rotation to get North up East left

  • mute_progression – Mute the printing of the progression percentage. Indeed sometimes the overwriting feature doesn’t work and one ends up with thousands of printed lines. Therefore muting it can be a good idea.

  • annuli_spacing – how to distribute the annuli radially. Currently three options. Constant (equally spaced), log (logarithmical expansion with r), and linear (linearly expansion with r)

  • compute_noise_cube – if True, compute the noise in each pixel assuming azimuthally uniform noise

Returns:

array of [array of 2D images (PSF subtracted)] using different number of KL basis vectors as

specified by numbasis. Shape of (b,N,y,x).

Note: this will be None if save_klipped is False

fmout_np: output of forward modelling. perturbmag: output indicating the magnitude of the linear perturbation to assess validity of KLIP FM aligned_center: (x, y) location indicating the star center for all images and FM after PSF subtraction

Return type:

sub_imgs

pyklip.fm.pertrurb_nospec(evals, evecs, original_KL, refs, models_ref)[source]

Perturb the KL modes using a model of the PSF but with no assumption on the spectrum. Useful for planets.

By no assumption on the spectrum it means that the spectrum has been factored out of Delta_KL following equation (4) of Laurent Pueyo 2016 noted bold “Delta Z_k^lambda (x)”. In order to get the actual perturbed KL modes one needs to multpily it by a spectrum.

This function fits each cube’s spectrum independently. So the effective spectrum size is N_wavelengths * N_cubes.

Parameters:
  • evals – array of eigenvalues of the reference PSF covariance matrix (array of size numbasis)

  • evecs – corresponding eigenvectors (array of size [p, numbasis])

  • orignal_KL – unpertrubed KL modes (array of size [numbasis, p])

  • Sel_wv – wv x N array of the the corresponding wavelength for each reference PSF

  • refs – N x p array of the N reference images that characterizes the extended source with p pixels

  • models_ref – N x p array of the N models corresponding to reference images. Each model should be normalized to unity (no flux information)

  • model_sci – array of size p corresponding to the PSF of the science frame

Returns:

perturbed KL modes but without the spectral info. delta_KL = spectrum x delta_Kl_nospec.

Shape is (numKL, wv, pix)

Return type:

delta_KL_nospec

pyklip.fm.perturb_nospec_modelsBased(evals, evecs, original_KL, refs, models_ref_list)[source]

Perturb the KL modes using a model of the PSF but with no assumption on the spectrum. Useful for planets.

By no assumption on the spectrum it means that the spectrum has been factored out of Delta_KL following equation (4) of Laurent Pueyo 2016 noted bold “Delta Z_k^lambda (x)”. In order to get the actual perturbed KL modes one needs to multpily it by a spectrum.

Effectively does the same thing as pertrurb_nospec() but in a different way. It injects models with dirac spectrum (all but one vanishing wavelength) and because of the linearity of the problem allow one de get reconstruct the perturbed KL mode for any spectrum. The difference however in the pertrurb_nospec() case is that the spectrum here is the asummed to be the same for all

cubes while pertrurb_nospec() fit each cube independently.

Parameters:
  • evals

  • evecs

  • original_KL

  • refs

  • models_ref

Returns:

delta_KL_nospec

pyklip.fm.perturb_specIncluded(evals, evecs, original_KL, refs, models_ref, return_perturb_covar=False)[source]

Perturb the KL modes using a model of the PSF but with the spectrum included in the model. Quicker than the others

Parameters:
  • evals – array of eigenvalues of the reference PSF covariance matrix (array of size numbasis)

  • evecs – corresponding eigenvectors (array of size [p, numbasis])

  • orignal_KL – unpertrubed KL modes (array of size [numbasis, p])

  • refs – N x p array of the N reference images that characterizes the extended source with p pixels

  • models_ref – N x p array of the N models corresponding to reference images. Each model should contain spectral informatoin

  • model_sci – array of size p corresponding to the PSF of the science frame

Returns:

perturbed KL modes. Shape is (numKL, wv, pix)

Return type:

delta_KL_nospec

pyklip.klip module

pyklip.klip.align_and_scale(img, new_center, old_center=None, scale_factor=1, dtype=<class 'float'>)[source]

Helper function that realigns and/or scales the image

Parameters:
  • img – 2D image to perform manipulation on

  • new_center – 2 element tuple (xpos, ypos) of new image center

  • old_center – 2 element tuple (xpos, ypos) of old image center

  • scale_factor

    how much the stretch/contract the image. Will we scaled w.r.t the new_center (done after relaignment). We will adopt the convention

    >1: stretch image (shorter to longer wavelengths) <1: contract the image (longer to shorter wvs) This means scale factor should be lambda_0/lambda where lambda_0 is the wavelength you want to scale to

Returns:

shifted and/or scaled 2D image

Return type:

resampled_img

pyklip.klip.calc_scaling(sats, refwv=18)[source]

Helper function that calculates the wavelength scaling factor from the satellite spot locations. Uses the movement of spots diagonally across from each other, to calculate the scaling in a (hopefully? tbd.) centering-independent way. This method is definitely temporary and will be replaced by better scaling strategies as we come up with them. Scaling is calculated as the average of (1/2 * sqrt((x_1-x_2)**2+(y_1-y_2))), over the two pairs of spots.

Parameters:
  • sats – [4 x Nlambda x 2] array of x and y positions for the 4 satellite spots

  • refwv – reference wavelength for scaling (optional, default = 20)

Returns:

Nlambda array of scaling factors

Return type:

scaling_factors

pyklip.klip.collapse_data(data, pixel_weights=None, axis=1, collapse_method='mean')[source]

Function to collapse multi-dimensional data along axis using collapse_method

Parameters:
  • data – (multi-dimension)arrays of 2D images or 3D cubes.

  • pixel_weights – ones if collapse method is not weighted collapse

  • axis – axis index along which to collapse

  • collapse_method – currently support ‘median’, ‘mean’, ‘weighted-mean’, ‘trimmed-mean’, ‘weighted-median’

Returns:

Collapsed data

pyklip.klip.define_annuli_bounds(annuli, IWA, OWA, annuli_spacing='constant')[source]

Defines the annuli boundaries radially

Parameters:
  • annuli – number of annuli

  • IWA – inner working angle (pixels)

  • OWA – outer working anglue (pixels)

  • annuli_spacing – how to distribute the annuli radially. Currently three options. Constant (equally spaced), log (logarithmical expansion with r), and linear (linearly expansion with r)

Returns:

array of 2-element tuples that specify the beginning and end radius of that annulus

Return type:

rad_bounds

pyklip.klip.estimate_movement(radius, parang0=None, parangs=None, wavelength0=None, wavelengths=None, mode=None)[source]

Estimates the movement of a hypothetical astrophysical source in ADI and/or SDI at the given radius and given reference parallactic angle (parang0) and reference wavelegnth (wavelength0)

Parameters:
  • radius – the radius from the star of the hypothetical astrophysical source

  • parang0 – the parallactic angle of the reference image (in degrees)

  • parangs – array of length N of the parallactic angle of all N images (in degrees)

  • wavelength0 – the wavelength of the reference image

  • wavelengths – array of length N of the wavelengths of all N images

  • NOTE – we expect parang0 and parangs to be either both defined or both None. Same with wavelength0 and wavelengths

  • mode – one of [‘ADI’, ‘SDI’, ‘ADI+SDI’] for ADI, SDI, or ADI+SDI

Returns:

array of length N of the distance an astrophysical source would have moved from the

reference image

Return type:

moves

pyklip.klip.high_pass_filter(img, filtersize=10)[source]

A FFT implmentation of high pass filter.

Parameters:
  • img – a 2D image

  • filtersize – size in Fourier space of the size of the space. In image space, size=img_size/filtersize

Returns:

the filtered image

Return type:

filtered

pyklip.klip.klip_math(sci, ref_psfs, numbasis, covar_psfs=None, return_basis=False, return_basis_and_eig=False)[source]

Helper function for KLIP that does the linear algebra

Parameters:
  • sci – array of length p containing the science data

  • ref_psfs – N x p array of the N reference PSFs that characterizes the PSF of the p pixels

  • numbasis – number of KLIP basis vectors to use (can be an int or an array of ints of length b)

  • covar_psfs – covariance matrix of reference psfs passed in so you don’t have to calculate it here

  • return_basis – If true, return KL basis vectors (used when onesegment==True)

  • return_basis_and_eig – If true, return KL basis vectors as well as the eigenvalues and eigenvectors of the covariance matrix. Used for KLIP Forward Modelling of Laurent Pueyo.

Returns:

array of shape (p,b) that is the PSF subtracted data for each of the b KLIP basis

cutoffs. If numbasis was an int, then sub_img_row_selected is just an array of length p

KL_basis: array of shape (max(numbasis),p). Only if return_basis or return_basis_and_eig is True. evals: Eigenvalues of the covariance matrix. The covariance matrix is assumed NOT to be normalized by (p-1).

Only if return_basis_and_eig is True.

evecs: Eigenvectors of the covariance matrix. The covariance matrix is assumed NOT to be normalized by (p-1).

Only if return_basis_and_eig is True.

Return type:

sub_img_rows_selected

pyklip.klip.make_polar_coordinates(x, y, center=[0, 0])[source]
Parameters:
  • x – meshgrid of x coordinates

  • y – meshgrid of y coordinates

  • center – new location of origin

Returns:

polar coordinates centered at the specified origin

pyklip.klip.meas_contrast(dat, iwa, owa, resolution, center=None, low_pass_filter=True)[source]

Measures the contrast in the image. Image must already be in contrast units and should be corrected for algorithm thoughput.

Parameters:
  • dat – 2D image - already flux calibrated

  • iwa – inner working angle

  • owa – outer working angle

  • resolution – size of noise resolution element in pixels (for speckle noise ~ FWHM or lambda/D) but it can be 1 pixel if limited by pixel-to-pixel noise.

  • center – location of star (x,y). If None, defaults the image size // 2.

  • low_pass_filter – if True, run a low pass filter. Can also be a float which specifices the width of the Gaussian filter (sigma). If False, no Gaussian filter is run

Returns:

tuple of separations in pixels and corresponding 5 sigma FPF

Return type:

(seps, contrast)

pyklip.klip.nan_gaussian_filter(img, sigma, ivar=None)[source]

Gaussian low-pass filter that handles nans

Parameters:
  • img – 2-D image

  • sigma – float specifiying width of Gaussian

  • ivar – inverse variance frame for the image, optional

Returns:

2-D image that has been smoothed with a Gaussian

Return type:

filtered

pyklip.klip.nan_map_coordinates_2d(img, yp, xp, mc_kwargs=None)[source]

scipy.ndimage.map_coordinates() that handles nans for 2-D transformations. Only works in 2-D!

Do NaN detection by defining any pixel in the new coordiante system (xp, yp) as a nan If any one of the neighboring pixels in the original image is a nan (e.g. (xp, yp) = (120.1, 200.1) is nan if either (120, 200), (121, 200), (120, 201), (121, 201) is a nan)

Parameters:
  • img (np.array) – 2-D image that is looking to be transformed

  • yp (np.array) – 2-D array of y-coordinates that the image is evaluated out

  • xp (np.array) – 2-D array of x-coordinates that the image is evaluated out

  • mc_kwargs (dict) – other parameters to pass into the map_coordinates function.

Returns:

2-D transformed image. Each pixel is evaluated at the (yp, xp) specified by xp and yp.

Return type:

transformed_img (np.array)

pyklip.klip.rotate(img, angle, center, new_center=None, flipx=False, astr_hdr=None)[source]

Rotate an image by the given angle about the given center. Optional: can shift the image to a new image center after rotation. Also can reverse x axis for those left

handed astronomy coordinate systems

Parameters:
  • img – a 2D image

  • angle – angle CCW to rotate by (degrees)

  • center – 2 element list [x,y] that defines the center to rotate the image to respect to

  • new_center – 2 element list [x,y] that defines the new image center after rotation

  • flipx – reverses x axis after rotation

  • astr_hdr – wcs astrometry header for the image

Returns:

new 2D image

Return type:

resampled_img

pyklip.nmf_imaging module

pyklip.nmf_imaging.NMFbff(trg, model, fracs=None)[source]

BFF subtraction. :param trg: :param model: :param fracs: (if need to be).

Returns:

best frac

pyklip.nmf_imaging.NMFcomponents(ref, ref_err=None, n_components=None, maxiters=1000.0, oneByOne=False, ignore_mask=None, path_save=None, recalculate=False)[source]

Returns the NMF components, where the rows contain the information. :param ref and ref_err should be: :type ref and ref_err should be: N, p :param ignore_mask: array of shape (N, p). mask pixels in each image that you don’t want to use. :param path_save: string, path to save the NMF components (at: path_save + ‘_comp.fits’) and coeffieients (at: path_save + ‘_coef.fits’) :param recalculate: boolean, whether to recalculate when path_save is provided

Returns:

NMf components (n_components * p).

pyklip.nmf_imaging.NMFmodelling(trg, components, n_components=None, mask_components=None, mask_data_imputation=None, trg_err=None, maxiters=1000.0, cube=False, trgThresh=0)[source]

NMF modeling. :param trg: 1D array, p pixels :param components: N * p, calculated using NMFcomponents. :param n_components: how many components do you want to use. If None, all the components will be used. :param cube: whether output a cube or not (increasing the number of components). :param trgThresh: ignore the regions with low photon counts. Especially when they are ~10^-15 or smaller. I chose 0 in this case.

Returns:

NMF model of the target.

pyklip.nmf_imaging.NMFsubtraction(trg, model, frac=1)[source]

NMF subtraction with a correction factor, frac.

pyklip.nmf_imaging.data_masked_only(data, mask=None)[source]

Return the data where the same regions are ignored in all the data :param data: (p, N) where N is the number of references, p is the number of pixels in each reference :param mask: 1d array containing only 1 and 0, with 0 will be ignored in the output

Returns:

(p_focused, N) where p_focused is the number of 1’s in mask

Return type:

data_focused

pyklip.nmf_imaging.data_masked_only_revert(data, mask=None)[source]

Return the data where the same regions were ignored in all the data :param data: (p_focused, N) where N is the number of references, p_focused is the number of 1’s in mask :param mask: 1d array containing only 1 and 0, with 0 was previously ignored in the input

Returns:

(p, N) where p is the number of pixels in each reference

Return type:

data_focused_revert

pyklip.nmf_imaging.nmf_math(sci, ref_psfs, sci_err=None, ref_psfs_err=None, componentNum=5, maxiters=100000.0, oneByOne=True, trg_type='disk', ignore_mask=None, path_save=None, recalculate=False, mask_data_imputation=None)[source]

Main NMF function for high contrast imaging. :param trg: target image, dimension: height * width. :type trg: 1D array :param refs: reference cube, dimension: referenceNumber * height * width. :type refs: 2D array :param trg_err: uncertainty for trg and refs, repectively. If None is given, the squareroot of the two arrays will be adopted. :param ref_err: uncertainty for trg and refs, repectively. If None is given, the squareroot of the two arrays will be adopted. :param componentNum: number of components to be used. Default: 5. Caution: choosing too many components will slow down the computation. :type componentNum: integer :param maxiters: number of iterations needed. Default: 10^5. :type maxiters: integer :param oneByOne: whether to construct the NMF components one by one. Default: True. :type oneByOne: boolean :param trg_type (string: “disk” or “d” for circumsetllar disks by Bin Ren, the user can use “planet” or “p” for planets): are we aiming at finding circumstellar disks or planets? :param default: “disk” or “d” for circumsetllar disks by Bin Ren, the user can use “planet” or “p” for planets): are we aiming at finding circumstellar disks or planets?

Returns:

NMF modeling result. Only the final subtraction result is returned.

Return type:

result (1D array)

pyklip.parallelized module

pyklip.parallelized.generate_noise_maps(imgs, aligned_center, dr, IWA=None, OWA=None, numthreads=None, pool=None)[source]

Create a noise map for each image. The noise levels are computed using azimuthally averaged noise in the images

Parameters:
  • imgs – array of shape (N,y,x) containing N images

  • aligned_center – [x,y] location of the center. All images should be aligned to common center

  • dr (float) – how mnay pixels wide the annulus to compute the noise should be

  • IWA (float) – inner working angle (how close to the center of the image to start). If none, this is 0

  • OWA (float) – outer working angle (if None, it is the entire image.)

  • numthreads – number of threads to be used

  • pool – multiprocessing thread pool (optional). To avoid repeatedly creating one when processing a list of images.

Returns:

array of shape (N,y,x) containing N noise maps

Return type:

noise_maps

pyklip.parallelized.high_pass_filter_imgs(imgs, numthreads=None, filtersize=10, pool=None)[source]

filters a sequences of images using a FFT

Parameters:
  • imgs – array of shape (N,y,x) containing N images

  • numthreads – number of threads to be used

  • filtersize – size in Fourier space of the size of the space. In image space, size=img_size/filtersize

  • pool – multiprocessing thread pool (optional). To avoid repeatedly creating one when processing a list of images.

Returns:

array of shape (N,y,x) containing the filtered images

Return type:

filtered

pyklip.parallelized.klip_dataset(dataset, mode='ADI+SDI', outputdir='.', fileprefix='', annuli=5, subsections=4, movement=3, numbasis=None, numthreads=None, minrot=0, calibrate_flux=False, aligned_center=None, annuli_spacing='constant', maxnumbasis=None, corr_smooth=1, spectrum=None, psf_library=None, highpass=False, lite=False, save_aligned=False, restored_aligned=None, dtype=None, algo='klip', skip_derot=False, time_collapse='mean', wv_collapse='mean', verbose=True)[source]

run klip on a dataset class outputted by an implementation of Instrument.Data

Parameters:
  • dataset – an instance of Instrument.Data (see instruments/ subfolder)

  • mode – some combination of ADI, SDI, and RDI (e.g. “ADI+SDI”, “RDI”)

  • outputdir – directory to save output files

  • fileprefix – filename prefix for saved files

  • anuuli – number of annuli to use for KLIP

  • subsections – number of sections to break each annuli into

  • movement – minimum amount of movement (in pixels) of an astrophysical source to consider using that image for a refernece PSF

  • numbasis – number of KL basis vectors to use (can be a scalar or list like). Length of b

  • numthreads – number of threads to use. If none, defaults to using all the cores of the cpu

  • minrot – minimum PA rotation (in degrees) to be considered for use as a reference PSF (good for disks)

  • calibrate_flux – if True calibrate flux of the dataset, otherwise leave it be

  • aligned_center – array of 2 elements [x,y] that all the KLIP subtracted images will be centered on for image registration

  • annuli_spacing – how to distribute the annuli radially. Currently three options. Constant (equally spaced), log (logarithmical expansion with r), and linear (linearly expansion with r)

  • maxnumbasis – if not None, maximum number of KL basis/correlated PSFs to use for KLIP. Otherwise, use max(numbasis)

  • corr_smooth (float) – size of sigma of Gaussian smoothing kernel (in pixels) when computing most correlated PSFs. If 0, no smoothing

  • spectrum – (only applicable for SDI) if not None, optimizes the choice of the reference PSFs based on the spectrum shape. - an array: of length N with the flux of the template spectrum at each wavelength. - a string: Currently only supports “methane” between 1 and 10 microns. Uses minmove to determine the separation from the center of the segment to determine contamination and the size of the PSF (TODO: make PSF size another quantity) (e.g. minmove=3, checks how much contamination is within 3 pixels of the hypothetical source) if smaller than 10%, (hard coded quantity), then use it for reference PSF

  • psf_library – if not None, a rdi.PSFLibrary object with a PSF Library for RDI

  • highpass – if True, run a Gaussian high pass filter (default size is sigma=imgsize/10) can also be a number specifying FWHM of box in pixel units

  • lite – if True, run a low memory version of the alogirhtm

  • save_aligned – Save the aligned and scaled images (as well as various wcs information), True/False

  • restore_aligned – The aligned and scaled images from a previous run of klip_dataset (usually restored_aligned = dataset.aligned_and_scaled)

  • dtype – data type of the arrays. Should be either ctypes.c_float(default) or ctypes.c_double

  • algo (str) – algorithm to use (‘klip’, ‘nmf’, ‘empca’, ‘none’). None will run no PSF subtraction.

  • skip_derot – if True, skips derotating the images. Note, the saved time-collapsed cubes may not make sense

  • time_collapse – how to collapse the data in time. Currently support: “mean”, “weighted-mean”, ‘median’, “weighted-median”

  • wv_collapse – how to collapse the data in wavelength. Currently support: ‘median’, ‘mean’, ‘trimmed-mean’

  • verbose (bool) – if True, print warning messages during KLIP process.

Returns

Saved files in the output directory Returns: nothing, but saves to dataset.output: (b, N, wv, y, x) 5D cube of KL cutoff modes (b), number of images

(N), wavelengths (wv), and spatial dimensions. Images are derotated. For ADI only, the wv is omitted so only 4D cube

pyklip.parallelized.klip_parallelized(imgs, centers, parangs, wvs, filenums, IWA, OWA=None, mode='ADI+SDI', annuli=5, subsections=4, movement=3, numbasis=None, aligned_center=None, numthreads=None, minrot=0, maxrot=360, annuli_spacing='constant', maxnumbasis=None, corr_smooth=1, spectrum=None, psf_library=None, psf_library_good=None, psf_library_corr=None, save_aligned=False, restored_aligned=None, dtype=None, algo='klip', compute_noise_cube=False, verbose=True)[source]

Multitprocessed KLIP PSF Subtraction

Parameters:
  • imgs – array of 2D images for ADI. Shape of array (N,y,x)

  • centers – N by 2 array of (x,y) coordinates of image centers

  • parangs – N length array detailing parallactic angle of each image

  • wvs – N length array of the wavelengths

  • filenums (np.array) – array of length N of the filenumber for each image

  • IWA – inner working angle (in pixels)

  • OWA – outer working angle (in pixels)

  • mode – one of [‘ADI’, ‘SDI’, ‘ADI+SDI’] for ADI, SDI, or ADI+SDI

  • anuuli – number of annuli to use for KLIP

  • subsections – number of sections to break each annuli into

  • movement – minimum amount of movement (in pixels) of an astrophysical source to consider using that image for a refernece PSF

  • numbasis – number of KL basis vectors to use (can be a scalar or list like). Length of b

  • aligned_center – array of 2 elements [x,y] that all the KLIP subtracted images will be centered on for image registration

  • numthreads – number of threads to use. If none, defaults to using all the cores of the cpu

  • minrot – minimum PA rotation (in degrees) to be considered for use as a reference PSF (good for disks)

  • maxrot – maximum PA rotation (in degrees) to be considered for use as a reference PSF (temporal variability)

  • annuli_spacing – how to distribute the annuli radially. Currently three options. Constant (equally spaced), log (logarithmical expansion with r), and linear (linearly expansion with r)

  • maxnumbasis – if not None, maximum number of KL basis/correlated PSFs to use for KLIP. Otherwise, use max(numbasis)

  • corr_smooth (float) – size of sigma of Gaussian smoothing kernel (in pixels) when computing most correlated PSFs. If 0, no smoothing

  • spectrum – if not None, a array of length N with the flux of the template spectrum at each wavelength. Uses minmove to determine the separation from the center of the segment to determine contamination and the size of the PSF (TODO: make PSF size another quanitity) (e.g. minmove=3, checks how much containmination is within 3 pixels of the hypothetical source) if smaller than 10%, (hard coded quantity), then use it for reference PSF

  • psf_library – array of (N_lib, y, x) with N_lib PSF library PSFs

  • psf_library_good – array of size N_lib indicating which N_good are good are selected in the passed in corr matrix

  • psf_library_corr – matrix of size N_sci x N_good with correlation between the target franes and the good RDI PSFs

  • save_aligned – Save the aligned and scaled images (as well as various wcs information), True/False

  • restore_aligned – The aligned and scaled images from a previous run of klip_dataset (usually restored_aligned = dataset.aligned_and_scaled)

  • dtype – data type of the arrays. Should be either ctypes.c_float(default) or ctypes.c_double

  • algo (str) – algorithm to use (‘klip’, ‘nmf’, ‘empca’)

  • compute_noise_cube – if True, compute the noise in each pixel assuming azimuthally uniform noise

Returns:

array of [array of 2D images (PSF subtracted)] using different number of KL basis vectors as

specified by numbasis. Shape of (b,N,y,x).

aligned_center: (x,y) specifying the common center the output images are aligned to

Return type:

sub_imgs

pyklip.parallelized.klip_parallelized_lite(imgs, centers, parangs, wvs, filenums, IWA, OWA=None, mode='ADI+SDI', annuli=5, subsections=4, movement=3, numbasis=None, aligned_center=None, numthreads=None, minrot=0, maxrot=360, annuli_spacing='constant', maxnumbasis=None, corr_smooth=1, spectrum=None, dtype=None, algo='klip', compute_noise_cube=False, **kwargs)[source]

multithreaded KLIP PSF Subtraction, has a smaller memory foot print than the original

Parameters:
  • imgs – array of 2D images for ADI. Shape of array (N,y,x)

  • centers – N by 2 array of (x,y) coordinates of image centers

  • parangs – N length array detailing parallactic angle of each image

  • wvs – N length array of the wavelengths

  • filenums (np.array) – array of length N of the filenumber for each image

  • IWA – inner working angle (in pixels)

  • OWA – outer working angle (in pixels)

  • mode – one of [‘ADI’, ‘SDI’, ‘ADI+SDI’] for ADI, SDI, or ADI+SDI

  • anuuli – number of annuli to use for KLIP

  • subsections – number of sections to break each annuli into

  • movement – minimum amount of movement (in pixels) of an astrophysical source to consider using that image for a refernece PSF

  • numbasis – number of KL basis vectors to use (can be a scalar or list like). Length of b

  • annuli_spacing – how to distribute the annuli radially. Currently three options. Constant (equally spaced), log (logarithmical expansion with r), and linear (linearly expansion with r)

  • maxnumbasis – if not None, maximum number of KL basis/correlated PSFs to use for KLIP. Otherwise, use max(numbasis)

  • corr_smooth (float) – size of sigma of Gaussian smoothing kernel (in pixels) when computing most correlated PSFs. If 0, no smoothing

  • aligned_center – array of 2 elements [x,y] that all the KLIP subtracted images will be centered on for image registration

  • numthreads – number of threads to use. If none, defaults to using all the cores of the cpu

  • minrot – minimum PA rotation (in degrees) to be considered for use as a reference PSF (good for disks)

  • maxrot – maximum PA rotation (in degrees) to be considered for use as a reference PSF (temporal variability)

  • spectrum – if not None, a array of length N with the flux of the template spectrum at each wavelength. Uses minmove to determine the separation from the center of the segment to determine contamination and the size of the PSF (TODO: make PSF size another quanitity) (e.g. minmove=3, checks how much containmination is within 3 pixels of the hypothetical source) if smaller than 10%, (hard coded quantity), then use it for reference PSF

  • kwargs – in case you pass it stuff that we don’t use in the lite version

  • dtype – data type of the arrays. Should be either ctypes.c_float (default) or ctypes.c_double

  • algo (str) – algorithm to use (‘klip’, ‘nmf’, ‘empca’)

  • compute_noise_cube – if True, compute the noise in each pixel assuming azimuthally uniform noise

Returns:

array of [array of 2D images (PSF subtracted)] using different number of KL basis vectors as

specified by numbasis. Shape of (b,N,y,x).

Return type:

sub_imgs

pyklip.parallelized.rotate_imgs(imgs, angles, centers, new_center=None, numthreads=None, flipx=False, hdrs=None, disable_wcs_rotation=False, pool=None)[source]

derotate a sequences of images by their respective angles

Parameters:
  • imgs – array of shape (N,y,x) containing N images

  • angles – array of length N with the angle to rotate each frame. Each angle should be CCW in degrees.

  • centers – array of shape N,2 with the [x,y] center of each frame

  • new_centers – a 2-element array with the new center to register each frame. Default is middle of image

  • numthreads – number of threads to be used

  • flipx – flip the x axis after rotation if desired

  • hdrs – array of N wcs astrometry headers

Returns:

array of shape (N,y,x) containing the derotated images

Return type:

derotated

pyklip.rdi module

class pyklip.rdi.PSFLibrary(data, aligned_center, filenames, correlation_matrix=None, wvs=None, compute_correlation=False)[source]

Bases: object

This is an PSF Library to use for reference differential imaging

master_library

aligned library of PSFs. 3-D cube of dim = [N, y, x]. Where N is ALL files

Type:

np.ndarray

aligned_center

a (x,y) coordinate specifying common center the library is aligned to

Type:

array-like

master_filenames

array of N filenames for each frame in the library. Should match with pyklip.instruments.Data.filenames for cross-matching

Type:

np.ndarray

master_correlation

N x N array of correlations between each 2 frames

Type:

np.ndarray

master_wvs

N wavelengths for each frame

Type:

np.ndarray

nfiles

the number of files in the PSF library

Type:

int

dataset
Type:

pyklip.instruments.Instrument.Data

correlation

N_data x M array of correlations between each 2 frames where M are the selected frames and N_data is the number of files in the dataset. Along the N_data dimension, files are ordered in the same way as the dataset object

Type:

np.ndarray

isgoodpsf

array of N indicating which M PSFs are good for this dataset

Type:

np.ndarray

add_new_dataset_to_library(dataset, collapse=False, verbose=False)[source]

Add all the files from a new dataset to the PSF library and add them to the correlation matrix. If a mask was used for the correlation matrix, use it here too.

NOTE: This routine already assumes that the data has been centered.

Parameters:

dataset (pyklip.instruments.Instrument.Data) –

prepare_library(dataset, badfiles=None)[source]

Prepare the PSF Library for an RDI reduction of a specific dataset by only taking the part of the library we need.

Parameters:

Returns:

save_correlation(filename, overwrite=False, clobber=None, format='fits')[source]

Saves self.correlation to a file specified by filename :param filename: filepath to store the correlation matrix :type filename: str :param overwrite: if true overwrite the previous correlation matrix :type overwrite: bool :param clobber: same as overwrite, but deprecated in astropy. :type clobber: bool :param format: type of file to store the correlation matrix as. Supports numpy?/fits?/pickle? (TBD) :type format: str

pyklip.spectra_management module

pyklip.spectra_management.LSQ_scale_model_PSF(PSF_template, planet_image, a)[source]
pyklip.spectra_management.calibrate_star_spectrum(template_spectrum, template_wvs, filter_name, magnitude, wvs)[source]

Scale the Pickles stellar spectrum of a star to the observed apparent magnitude and returns the stellar spectrum in physical units sampled at the specified wavelengths. Currently only supports 2MASS filters and magnitudes. TODO: implement a way to take magnitude error input and propogate the error to the final spectrum

Parameters:
  • template_spectrum – 1D array, model spectrum of the star with arbitrary units

  • template_wvs – 1D array, wavelengths at which the template_spectrum is smapled, in units of microns

  • filter_name – string, 2MASS filter, ‘J’, ‘H’, or ‘Ks’

  • magnitude – scalar, observed apparent magnitude of the star

  • mag_error – scalar or 1D array with 2 elements, error(s) of the magnitude, not yet implemented

  • wvs – 1D array, the wvs at which to sample the scaled spectrum, in units of angstroms

Returns:

1D array, scaled stellar spectrum sampled at wvs

Return type:

scaled_spectrum

pyklip.spectra_management.extract_planet_spectrum(cube_para, position, PSF_cube_para, method=None, filter=None, mute=True)[source]
pyklip.spectra_management.find_lower_nearest(array, value)[source]

Find the lower nearest element to value in array.

Parameters:
  • array – Array of value

  • value – Value for which one wants the lower value.

Returns:

(low_value, id) with low_value the closest lower value and id its index.

pyklip.spectra_management.find_nearest(array, value)[source]

Find the nearest element to value in array.

Parameters:
  • array – Array of value

  • value – Value for which one wants the closest value.

Returns:

(closest_value, id) with closest_value the closest lower value and id its index.

pyklip.spectra_management.find_upper_nearest(array, value)[source]

Find the upper nearest element to value in array.

Parameters:
  • array – Array of value

  • value – Value for which one wants the upper value.

Returns:

(up_value, id) with up_value the closest upper value and id its index.

pyklip.spectra_management.get_planet_spectrum(spectrum, wavelength, ori_wvs=None)[source]

Get the normalized spectrum of a planet for a GPI spectral band or any wavelengths array. Spectra are extraced from .flx files from Mark Marley et al’s models.

Parameters:
  • spectrum – Path of the .flx file containing the spectrum.

  • wavelength – array of wavelenths in microns (or string with GPI band ‘H’, ‘J’, ‘K1’, ‘K2’, ‘Y’). (When using GPI spectral band wavelength samples are linearly spaced between the first and the last wavelength of the band.)

Returns:

is the gpi sampling of the considered band in micrometer. spectrum: is the spectrum of the planet for the given band or wavelength array and normalized to unit mean.

Return type:

wavelengths

pyklip.spectra_management.get_specType(object_name, SpT_file_csv=None)[source]

Return the spectral type for a target based on Simbad or on the table in SpT_file

Parameters:
  • object_name – Name of the target: ie “c_Eri”

  • SpT_file – Filename (.csv) of the table containing the target names and their spectral type. Can be generated from quering Simbad. If None (default), the function directly tries to query Simbad.

Returns:

Spectral type

pyklip.spectra_management.get_star_spectrum(wvs_or_filter_name=None, star_type=None, temperature=None, mute=None)[source]

Get the spectrum of a star with given spectral type interpolating the pickles database. The spectrum is normalized to unit mean. It assumes type V star.

Inputs:
wvs_or_filter_name: array of wavelenths in microns (or string with GPI band ‘H’, ‘J’, ‘K1’, ‘K2’, ‘Y’).

(When using GPI spectral band wavelength samples are linearly spaced between the first and the last wavelength of the band.)

star_type: ‘A5’,’F4’,… Is ignored if temperature is defined.

If star_type is longer than 2 characters it is truncated.

temperature: temperature of the star. Overwrite star_type if defined.

Output:
(wavelengths, spectrum) where

wavelengths: Sampling in mum. spectrum: is the spectrum of the star for the given band.

Module contents