Add Stokes_cov_stat to fits and compute again P_debiased in plots

This commit is contained in:
2025-08-08 11:45:11 +02:00
parent e639695618
commit f4effac343
4 changed files with 223 additions and 142 deletions

View File

@@ -1301,12 +1301,12 @@ def compute_Stokes(data_array, error_array, data_mask, headers, FWHM=None, scale
# Statistical error: Poisson noise is assumed
sigma_flux = np.array([np.sqrt(flux / head["exptime"]) for flux, head in zip(pol_flux, pol_headers)])
s_IQU_stat = np.zeros(Stokes_cov.shape)
Stokes_cov_stat = np.zeros(Stokes_cov.shape)
for i in range(3):
s_IQU_stat[i, i] = np.sum([coeff_stokes[i, k] ** 2 * sigma_flux[k] ** 2 for k in range(len(sigma_flux))], axis=0)
Stokes_cov_stat[i, i] = np.sum([coeff_stokes[i, k] ** 2 * sigma_flux[k] ** 2 for k in range(len(sigma_flux))], axis=0)
for j in [k for k in range(3) if k > i]:
s_IQU_stat[i, j] = np.sum([coeff_stokes[i, k] * coeff_stokes[j, k] * sigma_flux[k] ** 2 for k in range(len(sigma_flux))], axis=0)
s_IQU_stat[j, i] = np.sum([coeff_stokes[i, k] * coeff_stokes[j, k] * sigma_flux[k] ** 2 for k in range(len(sigma_flux))], axis=0)
Stokes_cov_stat[i, j] = np.sum([coeff_stokes[i, k] * coeff_stokes[j, k] * sigma_flux[k] ** 2 for k in range(len(sigma_flux))], axis=0)
Stokes_cov_stat[j, i] = np.sum([coeff_stokes[i, k] * coeff_stokes[j, k] * sigma_flux[k] ** 2 for k in range(len(sigma_flux))], axis=0)
# Compute the derivative of each Stokes parameter with respect to the polarizer orientation
dIQU_dtheta = np.zeros(Stokes_cov.shape)
@@ -1359,19 +1359,19 @@ def compute_Stokes(data_array, error_array, data_mask, headers, FWHM=None, scale
)
# Compute the uncertainty associated with the polarizers' orientation (see Kishimoto 1999)
s_IQU_axis = np.zeros(Stokes_cov.shape)
Stokes_cov_axis = np.zeros(Stokes_cov.shape)
for i in range(3):
s_IQU_axis[i, i] = np.sum([dIQU_dtheta[i, k] ** 2 * globals()["sigma_theta"][k] ** 2 for k in range(len(globals()["sigma_theta"]))], axis=0)
Stokes_cov_axis[i, i] = np.sum([dIQU_dtheta[i, k] ** 2 * globals()["sigma_theta"][k] ** 2 for k in range(len(globals()["sigma_theta"]))], axis=0)
for j in [k for k in range(3) if k > i]:
s_IQU_axis[i, j] = np.sum(
Stokes_cov_axis[i, j] = np.sum(
[dIQU_dtheta[i, k] * dIQU_dtheta[j, k] * globals()["sigma_theta"][k] ** 2 for k in range(len(globals()["sigma_theta"]))], axis=0
)
s_IQU_axis[j, i] = np.sum(
Stokes_cov_axis[j, i] = np.sum(
[dIQU_dtheta[i, k] * dIQU_dtheta[j, k] * globals()["sigma_theta"][k] ** 2 for k in range(len(globals()["sigma_theta"]))], axis=0
)
# Add quadratically the uncertainty to the Stokes covariance matrix
Stokes_cov += s_IQU_axis + s_IQU_stat
Stokes_cov += Stokes_cov_axis + Stokes_cov_stat
# Save values to single header
header_stokes = pol_headers[0]
@@ -1445,10 +1445,10 @@ def compute_Stokes(data_array, error_array, data_mask, headers, FWHM=None, scale
header_stokes["PA_int"] = (PA_diluted, "Integrated polarization angle")
header_stokes["sPA_int"] = (np.ceil(PA_diluted_err * 10.0) / 10.0, "Integrated polarization angle error")
return Stokes, Stokes_cov, header_stokes, s_IQU_stat
return Stokes, Stokes_cov, header_stokes, Stokes_cov_stat
def compute_pol(Stokes, Stokes_cov, header_stokes, s_IQU_stat=None):
def compute_pol(Stokes, Stokes_cov, header_stokes, Stokes_cov_stat=None):
"""
Compute the polarization degree (in %) and angle (in deg) and their
respective errors from given Stokes parameters.
@@ -1524,7 +1524,7 @@ def compute_pol(Stokes, Stokes_cov, header_stokes, s_IQU_stat=None):
s_P_P = np.ones(Stokes[0].shape) * fmax
s_PA_P = np.ones(Stokes[0].shape) * fmax
maskP = np.logical_and(mask, P > 0.0)
if s_IQU_stat is not None:
if Stokes_cov_stat is not None:
# If IQU covariance matrix containing only statistical error is given propagate to P and PA
# Catch Invalid value in sqrt when diagonal terms are big
with warnings.catch_warnings(record=True) as _:
@@ -1532,13 +1532,15 @@ def compute_pol(Stokes, Stokes_cov, header_stokes, s_IQU_stat=None):
P[maskP]
/ Stokes[0][maskP]
* np.sqrt(
s_IQU_stat[0, 0][maskP]
- 2.0 / (Stokes[0][maskP] * P[maskP] ** 2) * (Stokes[1][maskP] * s_IQU_stat[0, 1][maskP] + Stokes[2][maskP] * s_IQU_stat[0, 2][maskP])
Stokes_cov_stat[0, 0][maskP]
- 2.0
/ (Stokes[0][maskP] * P[maskP] ** 2)
* (Stokes[1][maskP] * Stokes_cov_stat[0, 1][maskP] + Stokes[2][maskP] * Stokes_cov_stat[0, 2][maskP])
+ 1.0
/ (Stokes[0][maskP] ** 2 * P[maskP] ** 4)
* (
Stokes[1][maskP] ** 2 * s_IQU_stat[1, 1][maskP]
+ Stokes[2][maskP] ** 2 * s_IQU_stat[2, 2][maskP] * Stokes[1][maskP] * Stokes[2][maskP] * s_IQU_stat[1, 2][maskP]
Stokes[1][maskP] ** 2 * Stokes_cov_stat[1, 1][maskP]
+ Stokes[2][maskP] ** 2 * Stokes_cov_stat[2, 2][maskP] * Stokes[1][maskP] * Stokes[2][maskP] * Stokes_cov_stat[1, 2][maskP]
)
)
)
@@ -1546,9 +1548,9 @@ def compute_pol(Stokes, Stokes_cov, header_stokes, s_IQU_stat=None):
90.0
/ (np.pi * Stokes[0][maskP] ** 2 * P[maskP] ** 2)
* (
Stokes[1][maskP] ** 2 * s_IQU_stat[2, 2][maskP]
+ Stokes[2][maskP] * s_IQU_stat[1, 1][maskP]
- 2.0 * Stokes[1][maskP] * Stokes[2][maskP] * s_IQU_stat[1, 2][maskP]
Stokes[1][maskP] ** 2 * Stokes_cov_stat[2, 2][maskP]
+ Stokes[2][maskP] * Stokes_cov_stat[1, 1][maskP]
- 2.0 * Stokes[1][maskP] * Stokes[2][maskP] * Stokes_cov_stat[1, 2][maskP]
)
)
else:
@@ -1576,7 +1578,7 @@ def compute_pol(Stokes, Stokes_cov, header_stokes, s_IQU_stat=None):
return P, debiased_P, s_P, s_P_P, PA, s_PA, s_PA_P
def rotate_Stokes(Stokes, Stokes_cov, data_mask, header_stokes, s_IQU_stat=None, SNRi_cut=None):
def rotate_Stokes(Stokes, Stokes_cov, data_mask, header_stokes, Stokes_cov_stat=None, SNRi_cut=None):
"""
Use scipy.ndimage.rotate to rotate I_stokes to an angle, and a rotation
matrix to rotate Q, U of a given angle in degrees and update header
@@ -1642,16 +1644,16 @@ def rotate_Stokes(Stokes, Stokes_cov, data_mask, header_stokes, s_IQU_stat=None,
new_Stokes[:3, i, j] = np.dot(mrot, new_Stokes[:3, i, j])
new_Stokes_cov[:3, :3, i, j] = np.dot(mrot, np.dot(new_Stokes_cov[:3, :3, i, j], mrot.T))
if s_IQU_stat is not None:
s_IQU_stat = zeropad(s_IQU_stat, [*s_IQU_stat.shape[:-2], *shape])
new_s_IQU_stat = np.zeros((*s_IQU_stat.shape[:-2], *shape))
if Stokes_cov_stat is not None:
Stokes_cov_stat = zeropad(Stokes_cov_stat, [*Stokes_cov_stat.shape[:-2], *shape])
new_Stokes_cov_stat = np.zeros((*Stokes_cov_stat.shape[:-2], *shape))
for i in range(3):
for j in range(3):
new_s_IQU_stat[i, j] = sc_rotate(s_IQU_stat[i, j], ang, order=1, reshape=False, cval=0.0)
new_s_IQU_stat[i, i] = np.abs(new_s_IQU_stat[i, i])
new_Stokes_cov_stat[i, j] = sc_rotate(Stokes_cov_stat[i, j], ang, order=1, reshape=False, cval=0.0)
new_Stokes_cov_stat[i, i] = np.abs(new_Stokes_cov_stat[i, i])
for i in range(shape[0]):
for j in range(shape[1]):
new_s_IQU_stat[:3, :3, i, j] = np.dot(mrot, np.dot(new_s_IQU_stat[:3, :3, i, j], mrot.T))
new_Stokes_cov_stat[:3, :3, i, j] = np.dot(mrot, np.dot(new_Stokes_cov_stat[:3, :3, i, j], mrot.T))
# Update headers to new angle
mrot = np.array([[np.cos(-alpha), -np.sin(-alpha)], [np.sin(-alpha), np.cos(-alpha)]])
@@ -1701,8 +1703,8 @@ def rotate_Stokes(Stokes, Stokes_cov, data_mask, header_stokes, s_IQU_stat=None,
new_header_stokes["PA_int"] = (PA_diluted, "Integrated polarization angle")
new_header_stokes["sPA_int"] = (np.ceil(PA_diluted_err * 10.0) / 10.0, "Integrated polarization angle error")
if s_IQU_stat is not None:
return new_Stokes, new_Stokes_cov, new_data_mask, new_header_stokes, new_s_IQU_stat
if Stokes_cov_stat is not None:
return new_Stokes, new_Stokes_cov, new_data_mask, new_header_stokes, new_Stokes_cov_stat
else:
return new_Stokes, new_Stokes_cov, new_data_mask, new_header_stokes