def test_functional_ifu_prism():
"""Compare Nirspec instrument model with IDT model for IFU prism."""
# setup test
model_file = 'ifu_prism_functional_ESA_v1_20180619.txt'
hdu1 = create_nirspec_ifu_file(grating='PRISM',
filter='CLEAR',
gwa_xtil=0.35986012,
gwa_ytil=0.13448857,
gwa_tilt=37.1)
im = datamodels.ImageModel(hdu1)
refs = create_reference_files(im)
pipeline = nirspec.create_pipeline(im, refs, slit_y_range=[-0.55, 0.55])
w = wcs.WCS(pipeline)
im.meta.wcs = w
slit_wcs = nirspec.nrs_wcs_set_input(im, 0) # use slice 0
ins_file = get_file_path(model_file)
ins_tab = table.Table.read(ins_file, format='ascii')
slitx = [0] * 5
slity = [-.5, -.25, 0, .25, .5]
lam = np.array([.7e-7, 1e-6, 2e-6, 3e-6, 5e-6])
order, wrange = nirspec.get_spectral_order_wrange(im,
refs['wavelengthrange'])
im.meta.wcsinfo.sporder = order
im.meta.wcsinfo.waverange_start = wrange[0]
im.meta.wcsinfo.waverange_end = wrange[1]
# Slit to MSA entrance
# This includes the Slicer transform and the IFUFORE transform
slit2msa = slit_wcs.get_transform('slit_frame', 'msa_frame')
msax, msay, _ = slit2msa(slitx, slity, lam)
assert_allclose(slitx, ins_tab['xslitpos'])
assert_allclose(slity, ins_tab['yslitpos'])
assert_allclose(msax + 0.0073, ins_tab['xmsapos'],
rtol=1e-2) # expected offset
assert_allclose(msay + 0.0085, ins_tab['ymaspos'],
rtol=1e-2) # expected offset
# Slicer
slit2slicer = slit_wcs.get_transform('slit_frame', 'slicer')
x_slicer, y_slicer, _ = slit2slicer(slitx, slity, lam)
# MSA exit
# Applies the IFUPOST transform to coordinates at the Slicer
with datamodels.IFUPostModel(refs['ifupost']) as ifupost:
ifupost_transform = nirspec._create_ifupost_transform(ifupost.slice_0)
x_msa_exit, y_msa_exit = ifupost_transform(x_slicer, y_slicer, lam)
assert_allclose(x_msa_exit, ins_tab['xmsapos'])
assert_allclose(y_msa_exit, ins_tab['ymaspos'])
# Coordinates at Collimator exit
# Applies the Collimator forward transform to coordinates at the MSA exit
with datamodels.open(refs['collimator']) as col:
colx, coly = col.model.inverse(x_msa_exit, y_msa_exit)
assert_allclose(colx, ins_tab['xcoll'])
assert_allclose(coly, ins_tab['ycoll'])
# After applying direcitonal cosines
dircos = trmodels.Unitless2DirCos()
xcolDircosi, ycolDircosi, z = dircos(colx, coly)
assert_allclose(xcolDircosi, ins_tab['xcolDirCosi'])
assert_allclose(ycolDircosi, ins_tab['ycolDirCosi'])
# Slit to GWA entrance
# applies the Collimator forward, Unitless to Directional and 3D Rotation to MSA exit coordinates
with datamodels.DisperserModel(refs['disperser']) as disp:
disperser = nirspec.correct_tilt(disp, im.meta.instrument.gwa_xtilt,
im.meta.instrument.gwa_ytilt)
collimator2gwa = nirspec.collimator_to_gwa(refs, disperser)
x_gwa_in, y_gwa_in, z_gwa_in = collimator2gwa(x_msa_exit, y_msa_exit)
assert_allclose(x_gwa_in, ins_tab['xdispIn'])
# Slit to GWA out
# Runs slit--> slicer --> msa_exit --> collimator --> dircos --> rotation --> angle_from_grating equation
slit2gwa = slit_wcs.get_transform('slit_frame', 'gwa')
x_gwa_out, y_gwa_out, z_gwa_out = slit2gwa(slitx, slity, lam)
assert_allclose(x_gwa_out, ins_tab['xdispLaw'])
assert_allclose(y_gwa_out, ins_tab['ydispLaw'])
# CAMERA entrance (assuming direction is from sky to detector)
angles = [
disperser['theta_x'], disperser['theta_y'], disperser['theta_z'],
disperser['tilt_y']
]
rotation = trmodels.Rotation3DToGWA(angles,
axes_order="xyzy",
name='rotation')
dircos2unitless = trmodels.DirCos2Unitless()
gwa2cam = rotation.inverse | dircos2unitless
x_camera_entrance, y_camera_entrance = gwa2cam(x_gwa_out, y_gwa_out,
z_gwa_out)
assert_allclose(x_camera_entrance, ins_tab['xcamCosi'])
assert_allclose(y_camera_entrance, ins_tab['ycamCosi'])
# at FPA
with datamodels.CameraModel(refs['camera']) as camera:
x_fpa, y_fpa = camera.model.inverse(x_camera_entrance,
y_camera_entrance)
assert_allclose(x_fpa, ins_tab['xfpapos'])
assert_allclose(y_fpa, ins_tab['yfpapos'])
# at SCA
slit2sca = slit_wcs.get_transform('slit_frame', 'sca')
x_sca_nrs1, y_sca_nrs1 = slit2sca(slitx, slity, lam)
# At NRS2
with datamodels.FPAModel(refs['fpa']) as fpa:
x_sca_nrs2, y_sca_nrs2 = fpa.nrs2_model.inverse(x_fpa, y_fpa)
assert_allclose(x_sca_nrs1 + 1, ins_tab['i'])
assert_allclose(y_sca_nrs1 + 1, ins_tab['j'])
# at oteip
# Goes through slicer, ifufore, and fore transforms
slit2oteip = slit_wcs.get_transform('slit_frame', 'oteip')
x_oteip, y_oteip, _ = slit2oteip(slitx, slity, lam)
assert_allclose(x_oteip, ins_tab['xOTEIP'])
assert_allclose(y_oteip, ins_tab['yOTEIP'])
# at v2, v3 [in arcsec]
slit2v23 = slit_wcs.get_transform('slit_frame', 'v2v3')
v2, v3, _ = slit2v23(slitx, slity, lam)
v2 /= 3600
v3 /= 3600
assert_allclose(v2, ins_tab['xV2V3'])
assert_allclose(v3, ins_tab['yV2V3'])
def test_functional_ifu_grating():
"""Compare Nirspec instrument model with IDT model for IFU grating."""
# setup test
model_file = 'ifu_grating_functional_ESA_v1_20180619.txt'
hdul = create_nirspec_ifu_file(grating='G395H',
filter='F290LP',
gwa_xtil=0.35986012,
gwa_ytil=0.13448857)
im = datamodels.ImageModel(hdul)
refs = create_reference_files(im)
pipeline = nirspec.create_pipeline(im, refs, slit_y_range=[-0.55, 0.55])
w = wcs.WCS(pipeline)
im.meta.wcs = w
slit_wcs = nirspec.nrs_wcs_set_input(im, 0) # use slice 0
ins_file = get_file_path(model_file)
ins_tab = table.Table.read(ins_file, format='ascii')
slitx = [0] * 5
slity = [-.5, -.25, 0, .25, .5]
lam = np.array([2.9, 3.39, 3.88, 4.37, 5]) * 10**-6
order, wrange = nirspec.get_spectral_order_wrange(im,
refs['wavelengthrange'])
im.meta.wcsinfo.sporder = order
im.meta.wcsinfo.waverange_start = wrange[0]
im.meta.wcsinfo.waverange_end = wrange[1]
# Slit to MSA entrance
# This includes the Slicer transform and the IFUFORE transform
slit2msa = slit_wcs.get_transform('slit_frame', 'msa_frame')
msax, msay, _ = slit2msa(slitx, slity, lam)
assert_allclose(slitx, ins_tab['xslitpos'])
assert_allclose(slity, ins_tab['yslitpos'])
assert_allclose(msax + 0.0073, ins_tab['xmsapos'],
rtol=1e-2) # expected offset
assert_allclose(msay + 0.0085, ins_tab['ymaspos'],
rtol=1e-2) # expected offset
# Slicer
slit2slicer = slit_wcs.get_transform('slit_frame', 'slicer')
x_slicer, y_slicer, _ = slit2slicer(slitx, slity, lam)
# MSA exit
# Applies the IFUPOST transform to coordinates at the Slicer
with datamodels.IFUPostModel(refs['ifupost']) as ifupost:
ifupost_transform = nirspec._create_ifupost_transform(ifupost.slice_0)
x_msa_exit, y_msa_exit = ifupost_transform(x_slicer, y_slicer, lam)
assert_allclose(x_msa_exit, ins_tab['xmsapos'])
assert_allclose(y_msa_exit, ins_tab['ymaspos'])
# Computations are done using the eact form of the equations in the reports
# Part I of the Forward IFU-POST transform - the linear transform
xc_out = 0.0487158154447
yc_out = 0.00856211956976
xc_in = 0.000355277216
yc_in = -3.0089012e-05
theta = np.deg2rad(-0.129043957046)
factor_x = 0.100989874454
factor_y = 0.100405184145
# Slicer coordinates
xS = 0.000399999989895
yS = -0.00600000005215
x = xc_out + factor_x * (+cos(theta) * (xS - xc_in) + sin(theta) *
(yS - yc_in))
y = yc_out + factor_y * (-sin(theta) * (xS - xc_in) + cos(theta) *
(yS - yc_in))
# Forward IFU-POST II part - non-linear transform
lam = 2.9e-6
coef_names = [
f'c{x}_{y}' for x in range(6) for y in range(6) if x + y <= 5
]
y_forw = [
-82.3492267824, 29234.6982762, -540260.780853, 771881.305018,
-2563462.26848, 29914272.1164, 4513.04082605, -2212869.44311,
32875633.0303, -29923698.5288, 27293902.5636, -39820.4434726,
62431493.9962, -667197265.033, 297253538.182, -1838860.86305,
-777169857.2, 4514693865.7, 42790637.764, 3596423850.94, -260274017.448
]
y_forw_dist = [
188531839.97, -43453434864.0, 70807756765.8, -308272809909.0,
159768473071.0, 9712633344590.0, -11762923852.9, 3545938873190.0,
-4198643655420.0, 12545642983100.0, -11707051591600.0, 173091230285.0,
-108534069056000.0, 82893348097600.0, -124708740989000.0,
2774389757990.0, 1476779720300000.0, -545358301961000.0,
-93101557994100.0, -7536890639430000.0, 646310545048000.0
]
y_coeff = {}
for i, coef in enumerate(coef_names):
y_coeff[coef] = y_forw[i] + lam * y_forw_dist[i]
poly2d = astmodels.Polynomial2D(5, **y_coeff)
ifupost_y = poly2d(x, y)
assert_allclose(ifupost_y, ins_tab['ymaspos'][0])
assert_allclose(ifupost_y, y_msa_exit[0])
# reset 'lam'
lam = np.array([2.9, 3.39, 3.88, 4.37, 5]) * 10**-6
# Coordinates at Collimator exit
# Applies the Collimator forward transform to coordinates at the MSA exit
with datamodels.open(refs['collimator']) as col:
colx, coly = col.model.inverse(x_msa_exit, y_msa_exit)
assert_allclose(colx, ins_tab['xcoll'])
assert_allclose(coly, ins_tab['ycoll'])
# After applying direcitonal cosines
dircos = trmodels.Unitless2DirCos()
xcolDircosi, ycolDircosi, z = dircos(colx, coly)
assert_allclose(xcolDircosi, ins_tab['xcolDirCosi'])
assert_allclose(ycolDircosi, ins_tab['ycolDirCosi'])
# Slit to GWA entrance
# applies the Collimator forward, Unitless to Directional and 3D Rotation to MSA exit coordinates
with datamodels.DisperserModel(refs['disperser']) as disp:
disperser = nirspec.correct_tilt(disp, im.meta.instrument.gwa_xtilt,
im.meta.instrument.gwa_ytilt)
collimator2gwa = nirspec.collimator_to_gwa(refs, disperser)
x_gwa_in, y_gwa_in, z_gwa_in = collimator2gwa(x_msa_exit, y_msa_exit)
assert_allclose(x_gwa_in, ins_tab['xdispIn'])
# Slit to GWA out
# Runs slit--> slicer --> msa_exit --> collimator --> dircos --> rotation --> angle_from_grating equation
slit2gwa = slit_wcs.get_transform('slit_frame', 'gwa')
x_gwa_out, y_gwa_out, z_gwa_out = slit2gwa(slitx, slity, lam)
assert_allclose(x_gwa_out, ins_tab['xdispLaw'])
assert_allclose(y_gwa_out, ins_tab['ydispLaw'])
# CAMERA entrance (assuming direction is from sky to detector)
angles = [
disperser['theta_x'], disperser['theta_y'], disperser['theta_z'],
disperser['tilt_y']
]
rotation = trmodels.Rotation3DToGWA(angles,
axes_order="xyzy",
name='rotation')
dircos2unitless = trmodels.DirCos2Unitless()
gwa2cam = rotation.inverse | dircos2unitless
x_camera_entrance, y_camera_entrance = gwa2cam(x_gwa_out, y_gwa_out,
z_gwa_out)
assert_allclose(x_camera_entrance, ins_tab['xcamCosi'])
assert_allclose(y_camera_entrance, ins_tab['ycamCosi'])
# at FPA
with datamodels.CameraModel(refs['camera']) as camera:
x_fpa, y_fpa = camera.model.inverse(x_camera_entrance,
y_camera_entrance)
assert_allclose(x_fpa, ins_tab['xfpapos'])
assert_allclose(y_fpa, ins_tab['yfpapos'])
# at SCA
slit2sca = slit_wcs.get_transform('slit_frame', 'sca')
x_sca_nrs1, y_sca_nrs1 = slit2sca(slitx, slity, lam)
# At NRS2
with datamodels.FPAModel(refs['fpa']) as fpa:
x_sca_nrs2, y_sca_nrs2 = fpa.nrs2_model.inverse(x_fpa, y_fpa)
assert_allclose(x_sca_nrs1[:3] + 1, ins_tab['i'][:3])
assert_allclose(y_sca_nrs1[:3] + 1, ins_tab['j'][:3])
assert_allclose(x_sca_nrs2[3:] + 1, ins_tab['i'][3:])
assert_allclose(y_sca_nrs2[3:] + 1, ins_tab['j'][3:])
# at oteip
# Goes through slicer, ifufore, and fore transforms
slit2oteip = slit_wcs.get_transform('slit_frame', 'oteip')
x_oteip, y_oteip, _ = slit2oteip(slitx, slity, lam)
assert_allclose(x_oteip, ins_tab['xOTEIP'])
assert_allclose(y_oteip, ins_tab['yOTEIP'])
# at v2, v3 [in arcsec]
slit2v23 = slit_wcs.get_transform('slit_frame', 'v2v3')
v2, v3, _ = slit2v23(slitx, slity, lam)
v2 /= 3600
v3 /= 3600
assert_allclose(v2, ins_tab['xV2V3'])
assert_allclose(v3, ins_tab['yV2V3'])