Imager

class ehtim.imager.Imager(obs_in, init_im, prior_im=None, flux=None, data_term={'vis': 100}, reg_term={'simple': 1}, **kwargs)

A general interferometric imager.

check_limits()

Check image parameter consistency with observation.

check_params()

Check parameter consistency.

clipfloor_last()

Return last clip floor.

cp_uv_min_last()

Return last choice of minimal uvdistance for closure phases

dat_terms_last()

Return last used data terms.

debias_last()

Return last debias value.

flux_last()

Return last total flux constraint.

format_outim(outarr, pol_prim='I')

format the final image data into an Image object

init_imager()

Set up Stokes I imager.

init_last()

Return last initial image.

make_chisq_dict(imcur)

Make a dictionary of current chi^2 term values input is image array transformed to bounded values

make_chisqgrad_dict(imcur)

Make a dictionary of current chi^2 term gradient values input is image array transformed to bounded values

make_image(pol=None, grads=True, mf=False, **kwargs)

Make an image using current imager settings.

Parameters:

• pol (str) – which polarization to image

• grads (bool) – whether or not to use image gradients

• show_updates (bool) – whether or not to show imager progress

• update_interval (int) – step interval for plotting if show_updates=True

• mf (bool) – whether or not to do multifrequency (spectral index only for now)

• mf_order (int) – order for multifrequency spectral index imaging

• mf_order_pol (int) – order for multifrequency polarization fraction imaging

• mf_rm (int) – order for rotation measure imaging

• mf_cm (int) – order for conversion measure imaging

Returns:

output image

Return type:

(Image)

make_image_I(grads=True, niter=1, blur_frac=1, **kwargs)

Make Stokes I image using current imager settings.

make_image_IP(grads=True, niter=1, blur_frac=1, **kwargs)

Make Stokes I and P polarimetric image simultaneously using current imager settings.

make_image_IV(grads=True, niter=1, blur_frac=1, **kwargs)

Make Stokes I image using current imager settings.

make_image_P(grads=True, niter=1, blur_frac=1, **kwargs)

Make Stokes P polarimetric image using current imager settings.

make_image_V(grads=True, niter=1, blur_frac=1, **kwargs)

Make Stokes I image using current imager settings.

make_reg_dict(imcur)

Make a dictionary of current regularizer values input is image array transformed to bounded values

make_reggrad_dict(imcur)

Make a dictionary of current regularizer gradient values input is image array transformed to bounded values

maxit_last()

Return last max_iterations value.

maxset_last()

Return last choice of closure phase maximal/minimal set

mf_cm_last()

Return last choice for CM imaging

mf_last()

Return last choice for multifrequency imaging

mf_order_last()

Return last choice of order for multifrequency imaging

mf_order_pol_last()

Return last choice of order for multifrequency polarimetric imaging

mf_rm_last()

Return last choice for RM imaging

objfunc(imvec)

Current objective function.

objgrad(imvec)

Current objective function gradient.

obs_last()

Return last used observation.

property obs_next

the next Obsdata to be used in imaging

obslist_last()

Return last used observation.

out_last()

Return last result.

pflux_last()

Return last total linear polarimetric flux constraint.

plotcur(imvec, **kwargs)

Plot current image.

pol_last()

Return last polarization imaged.

prior_last()

Return last used prior image.

reffreq_last()

Return last choice of order for multifrequency imaging

reg_terms_last()

Return last used regularizer terms.

set_embed()

Set embedding matrix.

snrcut_last()

Return last snrcut value.

stop_last()

Return last convergence value.

systematic_cphase_noise_last()

Return last closure phase systematic noise value (in degree).

systematic_noise_last()

Return last systematic_noise value.

transform_last()

Return last image transform used.

vflux_last()

Return last total circular polarimetric flux constraint.

weighting_last()

Return last weighting value.

ehtim.imager.embed_imarr(imarr, mask, clipfloor=0.0, randomfloor=False)

Embeds a multidimensional image array into the size of boolean embed mask

ehtim.imager.make_initarr(image, mask, norm_init=False, flux=1, mf=False, pol=False, randompol_lin=False, randompol_circ=False, meanpol=0.2, sigmapol=0.01)

Make initial image array from image object, or initialize with default values

ehtim.imager.pack_imarr(imarr, which_solve)

pack image array imarr into 1D array vec for minimizaiton ignore quantities not solved for

ehtim.imager.transform_gradients(gradarr, imarr, transforms, which_solve)

Apply chain rule gradients for solver values for all polarizations gradarr is objective func gradients w/r/t physical variables imarr is the current image in solver variables

ehtim.imager.transform_imarr(imarr, transforms, which_solve)

Apply transformation from solver to physical values for all polarizations

ehtim.imager.transform_imarr_inverse(imarr, transforms, which_solve)

Apply inverse transformation from physical to solver values for all polarizations

ehtim.imager.unpack_imarr(vec, priorarr, which_solve)

unpack minimized vector vec into array, replace quantities not solved for with their initial values