Debiased pol_deg now with statistical error
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@@ -117,10 +117,9 @@ def main(target=None, proposal_id=None, infiles=None, output_dir="./data", crop=
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figtype = "_".join([figtype, "not_aligned"] if figtype != "" else ["not_aligned"])
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# Crop data to remove outside blank margins.
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data_array, error_array, headers = proj_red.crop_array(
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data_array, headers, step=5, null_val=0.0, inside=True, display=display_crop, savename=figname, plots_folder=plots_folder
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data_array, error_array, data_mask, headers = proj_red.crop_array(
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data_array, headers, step=5, null_val=0.0, crop=True, inside=True, display=display_crop, savename=figname, plots_folder=plots_folder
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)
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data_mask = np.ones(data_array[0].shape, dtype=bool)
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# Deconvolve data using Richardson-Lucy iterative algorithm with a gaussian PSF of given FWHM.
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if deconvolve:
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@@ -217,26 +216,30 @@ def main(target=None, proposal_id=None, infiles=None, output_dir="./data", crop=
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# FWHM of FOC have been estimated at about 0.03" across 1500-5000 Angstrom band, which is about 2 detector pixels wide
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# see Jedrzejewski, R.; Nota, A.; Hack, W. J., A Comparison Between FOC and WFPC2
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# Bibcode : 1995chst.conf...10J
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I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes = proj_red.compute_Stokes(
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I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes, coeff_stokes, sigma_flux = proj_red.compute_Stokes(
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data_array, error_array, data_mask, headers, FWHM=smoothing_FWHM, scale=smoothing_scale, smoothing=smoothing_function, transmitcorr=transmitcorr
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)
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, header_bkg = proj_red.compute_Stokes(
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, header_bkg, coeff_stokes, sigma_flux_bkg = proj_red.compute_Stokes(
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background, background_error, np.array(True).reshape(1, 1), headers, FWHM=None, scale=smoothing_scale, smoothing=smoothing_function, transmitcorr=False
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)
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# Step 3:
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# Rotate images to have North up
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if rotate_North:
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I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_stokes = proj_red.rotate_Stokes(
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I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_stokes, SNRi_cut=None
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I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_stokes, sigma_flux = proj_red.rotate_Stokes(
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I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_stokes, sigma_flux=sigma_flux, SNRi_cut=None
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)
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, data_mask_bkg, header_bkg = proj_red.rotate_Stokes(
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, np.array(True).reshape(1, 1), header_bkg, SNRi_cut=None
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, data_mask_bkg, header_bkg, sigma_flux_bkg = proj_red.rotate_Stokes(
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, np.array(True).reshape(1, 1), header_bkg, sigma_flux=sigma_flux_bkg, SNRi_cut=None
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)
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# Compute polarimetric parameters (polarization degree and angle).
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P, debiased_P, s_P, s_P_P, PA, s_PA, s_PA_P = proj_red.compute_pol(I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes)
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P_bkg, debiased_P_bkg, s_P_bkg, s_P_P_bkg, PA_bkg, s_PA_bkg, s_PA_P_bkg = proj_red.compute_pol(I_bkg, Q_bkg, U_bkg, S_cov_bkg, header_bkg)
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P, debiased_P, s_P, s_P_P, PA, s_PA, s_PA_P = proj_red.compute_pol(
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I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes, coeff_stokes=coeff_stokes, sigma_flux=sigma_flux
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)
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P_bkg, debiased_P_bkg, s_P_bkg, s_P_P_bkg, PA_bkg, s_PA_bkg, s_PA_P_bkg = proj_red.compute_pol(
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I_bkg, Q_bkg, U_bkg, S_cov_bkg, header_bkg, coeff_stokes=coeff_stokes, sigma_flux=sigma_flux_bkg
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)
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# Step 4:
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# Save image to FITS.
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@@ -224,7 +224,9 @@ def bin_ndarray(ndarray, new_shape, operation="sum"):
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return ndarray
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def crop_array(data_array, headers, error_array=None, data_mask=None, step=5, null_val=None, inside=False, display=False, savename=None, plots_folder=""):
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def crop_array(
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data_array, headers, error_array=None, data_mask=None, step=5, null_val=None, crop=True, inside=False, display=False, savename=None, plots_folder=""
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):
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"""
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Homogeneously crop an array: all contained images will have the same shape.
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'inside' parameter will decide how much should be cropped.
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@@ -256,6 +258,10 @@ def crop_array(data_array, headers, error_array=None, data_mask=None, step=5, nu
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If None, will be put to 75% of the mean value of the associated error
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array.
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Defaults to None.
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crop : boolean, optional
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If True, data_array will be cropped down to contain only relevant data.
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If False, this information will be kept in the crop_mask output.
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Defaults to True.
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inside : boolean, optional
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If True, the cropped image will be the maximum rectangle included
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inside the image. If False, the cropped image will be the minimum
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@@ -295,6 +301,9 @@ def crop_array(data_array, headers, error_array=None, data_mask=None, step=5, nu
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v_array[1] = np.max(vertex[:, 1]).astype(int)
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v_array[2] = np.min(vertex[:, 2]).astype(int)
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v_array[3] = np.max(vertex[:, 3]).astype(int)
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if data_mask is None:
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data_mask = np.zeros(data_array[0].shape).astype(bool)
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data_mask[v_array[0] : v_array[1], v_array[2] : v_array[3]] = True
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new_shape = np.array([v_array[1] - v_array[0], v_array[3] - v_array[2]])
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rectangle = [v_array[2], v_array[0], new_shape[1], new_shape[0], 0.0, "b"]
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@@ -352,11 +361,11 @@ def crop_array(data_array, headers, error_array=None, data_mask=None, step=5, nu
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)
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plt.show()
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if data_mask is not None:
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if crop:
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crop_mask = data_mask[v_array[0] : v_array[1], v_array[2] : v_array[3]]
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return crop_array, crop_error_array, crop_mask, crop_headers
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else:
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return crop_array, crop_error_array, crop_headers
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return data_array, error_array, data_mask, headers
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def deconvolve_array(data_array, headers, psf="gaussian", FWHM=1.0, scale="px", shape=None, iterations=20, algo="richardson"):
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@@ -1495,10 +1504,10 @@ def compute_Stokes(data_array, error_array, data_mask, headers, FWHM=None, scale
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header_stokes["PA_int"] = (PA_diluted, "Integrated polarization angle")
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header_stokes["sPA_int"] = (np.ceil(PA_diluted_err * 10.0) / 10.0, "Integrated polarization angle error")
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return I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes
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return I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes, coeff_stokes, sigma_flux
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def compute_pol(I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes):
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def compute_pol(I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes, coeff_stokes=None, sigma_flux=None):
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"""
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Compute the polarization degree (in %) and angle (in deg) and their
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respective errors from given Stokes parameters.
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@@ -1573,26 +1582,42 @@ def compute_pol(I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes):
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s_P[np.isnan(s_P)] = fmax
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s_PA[np.isnan(s_PA)] = fmax
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# Catch expected "OverflowWarning" as wrong pixel have an overflowing error
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with warnings.catch_warnings(record=True) as _:
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mask2 = P**2 >= s_P**2
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debiased_P = np.zeros(I_stokes.shape)
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debiased_P[mask2] = np.sqrt(P[mask2] ** 2 - s_P[mask2] ** 2)
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if (debiased_P > 1.0).any():
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print("WARNING : found {0:d} pixels for which debiased_P > 100%".format(debiased_P[debiased_P > 1.0].size))
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# Compute the total exposure time so that
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# I_stokes*exp_tot = N_tot the total number of events
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exp_tot = header_stokes["exptime"]
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# print("Total exposure time : {} sec".format(exp_tot))
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N_obs = I_stokes * exp_tot
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N_obs = I_stokes * float(header_stokes["exptime"])
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# Errors on P, PA supposing Poisson noise
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s_P_P = np.ones(I_stokes.shape) * fmax
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s_P_P[mask] = np.sqrt(2.0) / np.sqrt(N_obs[mask]) * 100.0
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s_PA_P = np.ones(I_stokes.shape) * fmax
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s_PA_P[mask2] = s_P_P[mask2] / (2.0 * P[mask2]) * 180.0 / np.pi
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maskP = np.logical_and(mask, P > 0.0)
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if coeff_stokes is not None and sigma_flux is not None:
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s_P_P[maskP] = (
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P[maskP]
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/ I_stokes[maskP]
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* np.sqrt(
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np.sum(
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[
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((coeff_stokes[1, i] * Q_stokes[maskP] + coeff_stokes[2, i] * U_stokes[maskP]) / (I_stokes[maskP] * P[maskP] ** 2) - coeff_stokes[0, i])
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** 2
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* sigma_flux[i][maskP] ** 2
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for i in range(sigma_flux.shape[0])
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],
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axis=0,
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)[0]
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)
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)
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else:
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s_P_P[mask] = np.sqrt(2.0 / N_obs[mask])
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s_PA_P[maskP] = s_P_P[maskP] / P[maskP] * 90.0 / np.pi
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# Catch expected "OverflowWarning" as wrong pixel have an overflowing error
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with warnings.catch_warnings(record=True) as _:
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mask2 = P**2 >= s_P_P**2
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debiased_P = np.zeros(I_stokes.shape)
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debiased_P[mask2] = np.sqrt(P[mask2] ** 2 - s_P_P[mask2] ** 2)
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if (debiased_P > 1.0).any():
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print("WARNING : found {0:d} pixels for which debiased_P > 100%".format(debiased_P[debiased_P > 1.0].size))
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# Nan handling :
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P[np.isnan(P)] = 0.0
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@@ -1605,7 +1630,7 @@ def compute_pol(I_stokes, Q_stokes, U_stokes, Stokes_cov, header_stokes):
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return P, debiased_P, s_P, s_P_P, PA, s_PA, s_PA_P
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def rotate_Stokes(I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_stokes, SNRi_cut=None):
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def rotate_Stokes(I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_stokes, sigma_flux=None, SNRi_cut=None):
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"""
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Use scipy.ndimage.rotate to rotate I_stokes to an angle, and a rotation
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matrix to rotate Q, U of a given angle in degrees and update header
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@@ -1698,6 +1723,9 @@ def rotate_Stokes(I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_st
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new_I_stokes[i, j], new_Q_stokes[i, j], new_U_stokes[i, j] = np.dot(mrot, np.array([new_I_stokes[i, j], new_Q_stokes[i, j], new_U_stokes[i, j]])).T
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new_Stokes_cov[:, :, i, j] = np.dot(mrot, np.dot(new_Stokes_cov[:, :, i, j], mrot.T))
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if sigma_flux is not None:
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new_sigma_flux = sc_rotate(zeropad(sigma_flux, (sigma_flux.shape[0], *shape)), ang, order=1, reshape=False, cval=0.0)
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# Update headers to new angle
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mrot = np.array([[np.cos(-alpha), -np.sin(-alpha)], [np.sin(-alpha), np.cos(-alpha)]])
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@@ -1751,7 +1779,10 @@ def rotate_Stokes(I_stokes, Q_stokes, U_stokes, Stokes_cov, data_mask, header_st
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new_header_stokes["PA_int"] = (PA_diluted, "Integrated polarization angle")
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new_header_stokes["sPA_int"] = (np.ceil(PA_diluted_err * 10.0) / 10.0, "Integrated polarization angle error")
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return new_I_stokes, new_Q_stokes, new_U_stokes, new_Stokes_cov, new_data_mask, new_header_stokes
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if sigma_flux is not None:
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return new_I_stokes, new_Q_stokes, new_U_stokes, new_Stokes_cov, new_data_mask, new_header_stokes, new_sigma_flux
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else:
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return new_I_stokes, new_Q_stokes, new_U_stokes, new_Stokes_cov, new_data_mask, new_header_stokes
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def rotate_data(data_array, error_array, data_mask, headers):
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