def regridData(baseCubeFits, otherDataFits, outDir, mask=False):
'''
regrids one data set to match the wcs of the base data set, which
is assumed to be a cube. The regridded data set can be either 2d
or 3d.
'''
# open the base cube
try:
baseCube = SpectralCube.read(baseCubeFits)
except:
print("Can't read in " + baseCubeFits + ".")
# determine ndim and bunit for other data sets
f = fits.open(otherDataFits)
ndim = f[0].header['NAXIS']
bunit = f[0].header['BUNIT']
f.close()
# output image name
newFits = os.path.join(
outDir,
os.path.basename(otherDataFits).replace('.fits', '_regrid.fits'))
# now regrid images appropriately
if ndim == 3:
# read in cube
otherCube = SpectralCube.read(otherDataFits)
# interpolate velocity axis. This needs to be done first.
regridCube = otherCube.spectral_interpolate(baseCube.spectral_axis)
regridCube.allow_huge_operations = True
newCube = regridCube.reproject(baseCube.header)
if mask:
# if greater than 0.0 set value to 1. otherwise 0.
newdata = np.where(newCube.unitless_filled_data[:, :, :] > 0.0, 1,
0)
finalCube = SpectralCube(newdata, newCube.wcs, mask=baseCube.mask)
else:
newdata = newCube.filled_data[:, :, :]
finalCube = SpectralCube(newdata, newCube.wcs, mask=baseCube.mask)
finalCube.with_spectral_unit(baseCube.spectral_axis.unit).write(
newFits, overwrite=True)
elif ndim == 2:
## consider using Projection.from_hdu then Projection.reproject here?
# regrid image
newcube = reproject_interp(
otherDataFits,
output_projection=baseCube.wcs.dropaxis(2),
shape_out=baseCube.wcs.dropaxis(2).array_shape,
order='nearest-neighbor',
return_footprint=False)
if mask:
# set to 1 where greater than 0.0.
newdata = np.where(newcube > 0.0, 1.0, 0.0)
else:
newdata = newcube
# get mask on original data
baseMask = baseCube.get_mask_array()
totalBaseMask = baseMask.max(axis=0)
newdata[np.invert(totalBaseMask)] = np.nan
# fix up header with input image units
outHdr = baseCube.wcs.dropaxis(2).to_header()
outHdr.append(('BUNIT', bunit))
# write out regridded data
fits.writeto(newFits, newdata, outHdr, overwrite=True)
else:
print("Number of dimensions of other data set is not 2 or 3.")
def rebaseline(filename, blorder=3,
baselineRegion=[slice(0, 262, 1), slice(-512, 0, 1)],
windowFunction=None, blankBaseline=False,
flagSpike=True, v0=None, **kwargs):
"""
Rebaseline a data cube using robust regression of Legendre polynomials.
Parameters
----------
filename : string
FITS filename of the data cube
blorder : int
Order of the polynomial to fit to the data
baselineRegion : list
List of slices defining the default region of the spectrum, in
channels, to be used for the baseline fitting.
windowFunction : function
Name of function to be used that will accept spectrum data, and
velocity axis and will return a binary mask of the channels to be used
in the baseline fitting. Extra **kwargs are passed to windowFunction
to do with as it must.
blankBaseline : boolean
Blank the baseline region on a per-spectrum basis
Returns
-------
Nothing. A new FITS file is written out with the suffix 'rebaseN' where N
is the baseline order
"""
cube = SpectralCube.read(filename)
originalUnit = cube.spectral_axis.unit
cube = cube.with_spectral_unit(u.km / u.s, velocity_convention='radio')
spaxis = cube.spectral_axis.to(u.km / u.s).value
goodposition = np.isfinite(cube.apply_numpy_function(np.max, axis=0))
y, x = np.where(goodposition)
outcube = np.zeros(cube.shape) * np.nan
RegionName = (filename.split('_'))[0]
if hasattr(windowFunction, '__call__'):
catalog = catalogs.GenerateRegions()
nuindex = np.arange(cube.shape[0])
runmin = nuindex[-1]
runmax = nuindex[0]
for thisy, thisx in console.ProgressBar(zip(y, x)):
spectrum = cube[:, thisy, thisx].value
if v0 is not None:
baselineIndex = windowFunction(spectrum, spaxis,
v0=v0, **kwargs)
elif hasattr(windowFunction, '__call__'):
_, Dec, RA = cube.world[0, thisy, thisx]
# This determines a v0 appropriate for the region
v0 = VlsrByCoord(RA.value, Dec.value, RegionName,
regionCatalog=catalog)
baselineIndex = windowFunction(spectrum, spaxis,
v0=v0, **kwargs)
else:
baselineIndex = np.zeros_like(spectrum,dtype=np.bool)
for ss in baselineRegion:
baselineIndex[ss] = True
runmin = np.min([nuindex[baselineIndex].min(), runmin])
runmax = np.max([nuindex[baselineIndex].max(), runmax])
# Use channel-to-channel difference as the noise value.
if flagSpike:
jumps = (spectrum - np.roll(spectrum, -1))
noise = mad1d(jumps) * 2**(-0.5)
baselineIndex *= (np.abs(jumps) < 5 * noise)
noise = mad1d((spectrum -
np.roll(spectrum, -2))[baselineIndex]) * 2**(-0.5)
else:
noise = mad1d((spectrum -
np.roll(spectrum, -2))[baselineIndex]) * 2**(-0.5)
if blankBaseline:
spectrum = robustBaseline(spectrum, baselineIndex,
blorder=blorder,
noiserms=noise)
spectrum[baselineIndex] = np.nan
outcube[:, thisy, thisx] = spectrum
else:
outcube[:, thisy, thisx] = robustBaseline(spectrum, baselineIndex,
blorder=blorder,
noiserms=noise)
outsc = SpectralCube(outcube, cube.wcs, header=cube.header)
outsc = outsc[runmin:runmax, :, :] # cut beyond baseline edges
# Return to original spectral unit
outsc = outsc.with_spectral_unit(originalUnit)
outsc.write(filename.replace('.fits', '_rebase{0}.fits'.format(blorder)),
overwrite=True)
def rebaseline(filename,
blorder=3,
baselineRegion=[slice(0, 800, 1),
slice(-800, 0, 1)],
windowFunction=None,
blankBaseline=False,
flagSpike=True,
v0=None,
VlsrByCoord=None,
verbose=False,
**kwargs):
"""
Rebaseline a data cube using robust regression of Legendre polynomials.
Parameters
----------
filename : string
FITS filename of the data cube
blorder : int
Order of the polynomial to fit to the data
baselineRegion : list
List of slices defining the default region of the spectrum, in
channels, to be used for the baseline fitting.
windowFunction : function
Name of function to be used that will accept spectrum data, and
velocity axis and will return a binary mask of the channels to be used
in the baseline fitting. Extra **kwargs are passed to windowFunction
to do with as it must.
blankBaseline : boolean
Blank the baseline region on a per-spectrum basis
Returns
-------
Nothing. A new FITS file is written out with the suffix 'rebaseN' where N
is the baseline order
"""
cube = SpectralCube.read(filename)
originalUnit = cube.spectral_axis.unit
cube = cube.with_spectral_unit(u.km / u.s, velocity_convention='radio')
spaxis = cube.spectral_axis.to(u.km / u.s).value
goodposition = np.isfinite(cube.apply_numpy_function(np.max, axis=0))
y, x = np.where(goodposition)
outcube = np.zeros(cube.shape) * np.nan
RegionName = (filename.split('/'))[-1]
RegionName = (RegionName.split('_'))[0]
nuindex = np.arange(cube.shape[0])
runmin = nuindex[-1]
runmax = nuindex[0]
if verbose:
pb = console.ProgressBar(len(y))
for thisy, thisx in zip(y, x):
spectrum = cube[:, thisy, thisx].value
if v0 is not None:
baselineIndex = windowFunction(spectrum, spaxis, v0=v0, **kwargs)
elif hasattr(windowFunction, '__call__') and \
hasattr(VlsrByCoord, '__call__'):
_, Dec, RA = cube.world[0, thisy, thisx]
# This determines a v0 appropriate for the region
v0 = VlsrByCoord(RA.value, Dec.value, RegionName, **kwargs)
baselineIndex = windowFunction(spectrum, spaxis, v0=v0, **kwargs)
else:
baselineIndex = np.zeros_like(spectrum, dtype=np.bool)
for ss in baselineRegion:
baselineIndex[ss] = True
runmin = np.min([nuindex[baselineIndex].min(), runmin])
runmax = np.max([nuindex[baselineIndex].max(), runmax])
# Use channel-to-channel difference as the noise value.
if flagSpike:
jumps = (spectrum - np.roll(spectrum, -1))
noise = mad1d(jumps) * 2**(-0.5)
baselineIndex *= (np.abs(jumps) < 5 * noise)
noise = mad1d(
(spectrum - np.roll(spectrum, -2))[baselineIndex]) * 2**(-0.5)
else:
noise = mad1d(
(spectrum - np.roll(spectrum, -2))[baselineIndex]) * 2**(-0.5)
if blankBaseline:
spectrum = robustBaseline(spectrum,
baselineIndex,
blorder=blorder,
noiserms=noise)
spectrum[baselineIndex] = np.nan
outcube[:, thisy, thisx] = spectrum
else:
outcube[:, thisy, thisx] = robustBaseline(spectrum,
baselineIndex,
blorder=blorder,
noiserms=noise)
if verbose:
pb.update()
outsc = SpectralCube(outcube,
cube.wcs,
header=cube.header,
meta={'BUNIT': cube.header['BUNIT']})
outsc = outsc[runmin:runmax, :, :] # cut beyond baseline edges
# Return to original spectral unit
outsc = outsc.with_spectral_unit(originalUnit)
outsc.write(filename.replace('.fits', '_rebase{0}.fits'.format(blorder)),
overwrite=True)
def get_best_2comp_residual(reg):
modbest = get_best_2comp_model(reg)
best_res = reg.ucube.cube._data - modbest
res_cube = SpectralCube(best_res, reg.ucube.cube.wcs)
res_cube = res_cube.with_spectral_unit(u.km / u.s, velocity_convention='radio')
return res_cube
def save_best_2comp_fit(reg):
# should be renamed to determine_best_2comp_fit or something along that line
# currently use np.nan for pixels with no models
ncomp = [1, 2]
# ideally, a copy function should be in place of reloading
# a new Region object is created start fresh on some of the functions (e.g., aic comparison)
reg_final = Region(reg.cubePath, reg.paraNameRoot, reg.paraDir)
# start out clean, especially since the deepcopy function doesn't work well for pyspeckit cubes
# load the file based on the passed in reg, rather than the default
for nc in ncomp:
if not str(nc) in reg.ucube.pcubes:
reg_final.load_fits(ncomp=[nc])
else:
# load files using paths from reg if they exist
print("loading model from: {}".format(reg.ucube.paraPaths[str(nc)]))
reg_final.ucube.load_model_fit(filename=reg.ucube.paraPaths[str(nc)], ncomp=nc)
pcube_final = reg_final.ucube.pcubes['2'].copy('deep')
# make the 2-comp para maps with the best fit model
lnk21 = reg_final.ucube.get_AICc_likelihood(2, 1)
mask = lnk21 > 5
print("2comp pix: {}".format(np.sum(mask)))
pcube_final.parcube[:4, ~mask] = reg_final.ucube.pcubes['1'].parcube[:4, ~mask].copy()
pcube_final.errcube[:4, ~mask] = reg_final.ucube.pcubes['1'].errcube[:4, ~mask].copy()
pcube_final.parcube[4:8, ~mask] = np.nan
pcube_final.errcube[4:8, ~mask] = np.nan
lnk10 = reg_final.ucube.get_AICc_likelihood(1, 0)
mask = lnk10 > 5
pcube_final.parcube[:, ~mask] = np.nan
pcube_final.errcube[:, ~mask] = np.nan
# use the default file formate to save the finals
nc = 2
if not str(nc) in reg_final.ucube.paraPaths:
reg_final.ucube.paraPaths[str(nc)] = '{}/{}_{}vcomp.fits'.format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot, nc)
savename = "{}_final.fits".format(os.path.splitext(reg_final.ucube.paraPaths['2'])[0])
UCube.save_fit(pcube_final, savename=savename, ncomp=2)
hdr2D =reg.ucube.cube.wcs.celestial.to_header()
# save the lnk21 map
savename = "{}/{}.fits".format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot.replace("para","lnk21"))
save_map(lnk21, hdr2D, savename)
# save the lnk10 map
savename = "{}/{}.fits".format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot.replace("para","lnk10"))
save_map(lnk10, hdr2D, savename)
# create and save the lnk20 map for reference:
lnk20 = reg_final.ucube.get_AICc_likelihood(2, 0)
savename = "{}/{}.fits".format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot.replace("para","lnk20"))
save_map(lnk20, hdr2D, savename)
# save the SNR map
snr_map = get_best_2comp_snr_mod(reg_final)
savename = "{}/{}.fits".format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot.replace("para","SNR"))
save_map(snr_map, hdr2D, savename)
# create moment0 map
modbest = get_best_2comp_model(reg_final)
cube_mod = SpectralCube(data=modbest, wcs=reg_final.ucube.pcubes['2'].wcs.copy(),
header=reg_final.ucube.pcubes['2'].header.copy())
# make sure the spectral unit is in km/s before making moment maps
cube_mod = cube_mod.with_spectral_unit('km/s', velocity_convention='radio')
mom0_mod = cube_mod.moment0()
savename = "{}/{}.fits".format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot.replace("para", "model_mom0"))
mom0_mod.write(savename, overwrite=True)
# created masked mom0 map with model as the mask
mom0 = UCube.get_masked_moment(cube=reg_final.ucube.cube, model=modbest, order=0, expand=20, mask=None)
savename = "{}/{}.fits".format(reg_final.ucube.paraDir, reg_final.ucube.paraNameRoot.replace("para", "mom0"))
mom0.write(savename, overwrite=True)
# save reduced chi-squred maps
# would be useful to check if 3rd component is needed
savename = "{}/{}.fits".format(reg_final.ucube.paraDir,
reg_final.ucube.paraNameRoot.replace("para", "chi2red_final"))
chi_map = UCube.get_chisq(cube=reg_final.ucube.cube, model=modbest, expand=20, reduced=True, usemask=True,
mask=None)
save_map(chi_map, hdr2D, savename)
# save reduced chi-squred maps for 1 comp and 2 comp individually
chiRed_1c = reg_final.ucube.get_reduced_chisq(1)
chiRed_2c = reg_final.ucube.get_reduced_chisq(2)
savename = "{}/{}.fits".format(reg_final.ucube.paraDir,
reg_final.ucube.paraNameRoot.replace("para", "chi2red_1c"))
save_map(chiRed_1c, hdr2D, savename)
savename = "{}/{}.fits".format(reg_final.ucube.paraDir,
reg_final.ucube.paraNameRoot.replace("para", "chi2red_2c"))
save_map(chiRed_2c, hdr2D, savename)
return reg
# --------------------------------------------------- #
# Find the (col,row) min/max limits of valid spaxels. #
# Min/max will be used to crop the data and the WCS. #
# --------------------------------------------------- #
wcsMinMax = pixMinMax(validPixels)
# --------------------------------------------- #
# Build the spectral cube using the contSubCube #
# --------------------------------------------- #
# NaNs and data to be ignored are FALSE.
specCube = SpectralCube(data,pacsWcs,mask=cubeMask,fill_value=1.)
# For convenience, convert the X-axis to km/s
# (WCSLIB automatically converts to m/s even if you give it km/s)
specCube = specCube.with_spectral_unit(u.km/u.s)
# --------------------------------------------- #
# Build the pySpecCube using the spectral cube. #
# --------------------------------------------- #
# NaN values are FALSE in the mask.
pyCube = pyspeckit.Cube(cube=specCube,maskmap=np.ma.getmask(falseMask[mid,:,:]))
# -------------------------------- #
# Set up for line profile fitting. #
# -------------------------------- #
# Build the guesses array
gc = buildGuessCube((nCols,nRows),
def deblend(para,
specCubeRef,
vmin=4.0,
vmax=11.0,
f_spcsamp=None,
tau_wgt=0.1,
n_cpu=None):
'''
Deblend hyperfine structures in a cube based on fitted models, i.e., reconstruct the fitted model with Gaussian
lines with optical depths accounted for (e.g., similar to CO (J = 0-1))
:param para: <ndarray>
The fitted parameters in the order of vel, width, tex, and tau for each velocity slab.
(Note: the size of the z axis for para must thus be in the multiple of 4)
:param specCubeRef: <SpectralCube.Cube>
The reference cube from which the deblended cube is constructed from
:param vmin: <float>
The lower veloicty limit on the deblended cube in the unit of km/s
:param vmax: <float>
The upper veloicty limit on the deblended cube in the unit of km/s
:param f_spcsamp: <int>
The scaling factor for the spectral sampling relative the reference cube
(e.g., f_spcsamp = 2 give you twice the spectral resolution)
:param tau_wgt:
The scaling factor for the input tau
(e.g., tau_wgt = 0.1 better represents the true optical depth of a NH3 (1,1) hyperfine group than the
"fitted tau")
:param n_cpu: <int>
The number of cpus to use. If None, defaults to all the cpus available minus one.
:return mcube: <SpectralCube.Cube>
The deblended cube
'''
# open the reference cube file
cube = specCubeRef
cube = cube.with_spectral_unit(u.km / u.s, velocity_convention='radio')
# trim the cube to the specified velocity range
cube = cube.spectral_slab(vmin * u.km / u.s, vmax * u.km / u.s)
# generate an empty SpectralCube to house the deblended cube
if f_spcsamp is None:
deblend = np.zeros(cube.shape)
hdr = cube.wcs.to_header()
wcs_new = cube.wcs
else:
deblend = np.zeros(
(cube.shape[0] * int(f_spcsamp), cube.shape[1], cube.shape[2]))
wcs_new = cube.wcs.deepcopy()
# adjust the spectral reference value
wcs_new.wcs.crpix[2] = wcs_new.wcs.crpix[2] * int(f_spcsamp)
# adjust the spaxel size
wcs_new.wcs.cdelt[2] = wcs_new.wcs.cdelt[2] / int(f_spcsamp)
hdr = wcs_new.to_header()
# retain the beam information
hdr['BMAJ'] = cube.header['BMAJ']
hdr['BMIN'] = cube.header['BMIN']
hdr['BPA'] = cube.header['BPA']
mcube = SpectralCube(deblend, wcs_new, header=hdr)
# convert back to an unit that the ammonia hf model can handle (i.e. Hz) without having to create a
# pyspeckit.spectrum.units.SpectroscopicAxis object (which runs rather slow for model building in comparison)
mcube = mcube.with_spectral_unit(u.Hz, velocity_convention='radio')
xarr = mcube.spectral_axis
yy, xx = np.indices(para.shape[1:])
# a pixel is valid as long as it has a single finite value
isvalid = np.any(np.isfinite(para), axis=0)
valid_pixels = zip(xx[isvalid], yy[isvalid])
def model_a_pixel(xy):
x, y = int(xy[0]), int(xy[1])
# nh3_vtau_singlemodel_deblended takes Hz as the spectral unit
models = [
nh3_deblended.nh3_vtau_singlemodel_deblended(xarr,
Tex=tex,
tau=tau * tau_wgt,
xoff_v=vel,
width=width)
for vel, width, tex, tau in zip(para[::4, y, x], para[1::4, y, x],
para[2::4, y, x], para[3::4, y, x])
]
mcube._data[:, y, x] = np.nansum(np.array(models), axis=0)
return ((x, y), mcube._data[:, y, x])
if n_cpu is None:
n_cpu = cpu_count() - 1
else:
n_cpu = 1
if n_cpu > 1:
print("------------------ deblending cube -----------------")
print("number of cpu used: {}".format(n_cpu))
sequence = [(x, y) for x, y in valid_pixels]
result = parallel_map(model_a_pixel, sequence, numcores=n_cpu)
merged_result = [
core_result for core_result in result if core_result is not None
]
for mr in merged_result:
((x, y), model) = mr
x = int(x)
y = int(y)
mcube._data[:, y, x] = model
else:
for xy in ProgressBar(list(valid_pixels)):
model_a_pixel(xy)
# convert back to km/s in units before saving
mcube = mcube.with_spectral_unit(u.km / u.s, velocity_convention='radio')
gc.collect()
print("--------------- deblending completed ---------------")
return mcube
