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Sunmish/fluxtools.py

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Measure integrated flux densities in images.
Raw
fluxtools.py
# TODO:
# Add precision options. Currently values are returned at arbitrary precision.
# Add `strip_extra_axes` function for use when reading in FITS images.
# Clean up read_fits and associated FITS file handling functions.
# Fix up documentation.
# This code is years worth of additions and changes that represent my own 'journey' in learning python
# and studying radio astronomy - so some (a lot) of it is horribly ineffecient.
import numpy as np
import math
import os
import sys
from astropy.io import fits # For handling FITS files.
from astropy.wcs import WCS # For computing LAS/positions.
from astropy.wcs.utils import proj_plane_pixel_scales
from astropy.coordinates import SkyCoord # For cross-referencing.
# SkyCoord or coordinates are returning import errors?
# This is needed for `measure_tree` - finding a source in a catalogue.
from astropy import units as u
from scipy.special import erf
import logging
logging.basicConfig(format="%(levelname)s (%(module)s): %(message)s", \
level=logging.INFO)
units = {"arcsec": u.arcsec, \
"arcmin": u.arcmin, \
"deg" : u.degree, \
"degree": u.degree, \
"as" : u.arcsec, \
"am" : u.arcmin, \
"radian": u.radian, \
"rad" : u.radian
}
# def output_formatter(source_number=None,
# int_flux=None,
# err_int_flux=None,
# peak_flux=None,
# avg_flux=None,
# npix=None,
# weight_coords=None,
# bright_coords=None,
# area=None,
# las=None,
# offset=None)
def angular_distance(coords1, coords2):
"""Get the angular distance between a set of RA, DEC coordinates in [dd].
Uncessary because of SkyCoord?
"""
cos_angle = math.sin(math.radians(coords1[1])) * \
math.sin(math.radians(coords2[1])) + \
math.cos(math.radians(coords1[1])) * \
math.cos(math.radians(coords2[1])) * \
math.cos(math.radians(coords1[0]) - math.radians(coords2[0]))
try:
gamma = math.degrees(math.acos(cos_angle))
except ValueError:
gamma = math.degrees(math.acos(min(1, max(cos_angle, -1))))
return gamma
def gaussian_blob_correction(peak, rms, sigma):
"""https://ui.adsabs.harvard.edu/abs/2012MNRAS.425..979H/abstract
"""
snr = peak / rms
eta = (erf(np.sqrt(-np.log((sigma / snr)))))**2
err_eta = np.abs(eta - (erf(np.sqrt(-np.log((sigma / ((peak-rms)/rms))))))**2)
return eta, err_eta
def dirtybias_correction(model_flux, residual_flux, source_bpp,
clean_bias_factor=1.,
clean_bias_std=0.):
"""
"""
model_flux = np.asarray(model_flux)
model_flux[np.where(model_flux < 0.)] = 0.
total_model_flux = np.nansum(model_flux)
print(">>> model flux: {} Jy".format(total_model_flux))
residual_flux = np.asarray(residual_flux)
residual_flux[np.where(residual_flux < 0.)] = 0.
total_residual_flux = np.nansum(residual_flux / source_bpp)
print(">>> residual flux: {} ({}) Jy".format(total_residual_flux,
total_residual_flux/clean_bias_factor))
total_model_flux += (total_residual_flux/clean_bias_factor)
residual_err = clean_bias_std*total_residual_flux
print(">>> model + residual flux {} Jy".format(total_model_flux))
print(">>> residual error {} Jy".format(residual_err))
return total_model_flux, residual_err
# https://stackoverflow.com/a/61629292/3293881 @Ehsan
def norm_method(arr, point):
point = np.asarray(point)
return np.linalg.norm(np.indices(arr.shape, sparse=True)-point)
def order_boundaries(coords):
"""Order boundary coordinates based on nearest-neighbours.
Only used for polygon annotations that are not too messy.
"""
un_x = [coord[0] for coord in coords]
un_y = [coord[1] for coord in coords]
ord_coord = [(un_x.pop(0), un_y.pop(0))]
for x, y in ord_coord:
init = True
index = None
for i in range(len(un_x)):
d = np.sqrt((x-un_x[i])**2 + (y-un_y[i])**2)
if init:
diff = d
index = i
init = False
elif d < diff:
diff = d
index = i
else:
pass
if index is None:
ord_coord.append(ord_coord[0])
break
else:
ord_coord.append((un_x.pop(index), un_y.pop(index)))
return ord_coord
def kvis_polygon(region, r_index=0):
"""Get coordinate list for polygon (CLINES) in annotation file.
TDOD: ds9 version?
"""
count = 0
f = open(region, "r")
lines = f.readlines()
polygons = []
for line in lines:
if "clines" in line.lower():
polygons.append(line)
poly = polygons[r_index] # If there are more than one cline entries.
bits = poly.split(" ")
coords = []
for i in range(1, len(bits)-1, 2):
coords.append((float(bits[i]), float(bits[i+1])))
f.close()
return coords
def pix_to_world(x, y, wcs):
"""Convenience function for astropy's all_pix2world."""
sub_wcs = wcs.sub(["longitude", "latitude"])
if not isinstance(x, np.ndarray):
x, y = np.asarray(x), np.asarray(y)
ra, dec = sub_wcs.all_pix2world(y, x, 0)
return ra, dec
def world_to_pix(ra, dec, warray, naxis):
"""A wrapper for astropy's all_world2pix.
This helps with issues where NAXIS > 2.
Returns lists if the input pixel coordinates are lists/arrays.
TODO: use sub_wcs
"""
if (not isinstance(ra, list)) and (not isinstance(ra, np.ndarray)):
ra, dec = [ra], [dec]
# if naxis == 2:
y, x = warray.all_world2pix(ra, dec, 0)
# elif naxis == 3:
# y, x, _ = warray.all_world2pix(ra, dec, np.ones_like(ra), 0)
# elif naxis == 4:
# y, x, _, _ = warray.all_world2pix(ra, dec, np.ones_like(ra), \
# np.ones_like(ra), 0)
# else:
# raise ValueError(">>> NAXIS must be 2, 3, or 4.")
if len(x) == 1: x, y = x[0], y[0]
return x, y
def get_hdulist(fitsimage):
"""Get HDUList object from filepath or form HDUList object."""
if isinstance(fitsimage, str):
if not fitsimage.endswith(".fits"): fitsimage += ".fits"
hdulist = fits.open(fitsimage)
opened = True
elif isinstance(fitsimage, fits.HDUList):
hdulist = fitsimage
opened = False
else:
raise ValueError("FITS image must be a filename/path or an " \
"astropy.io.fits.HDUList object.")
return hdulist, opened
def strip_naxis(fitsimage, outname=None, strip_wcs=True):
"""Strip additional axes from FITS file.
Strips axes 3 and/or 4 if present.
"""
image, opened = get_hdulist(fitsimage)
try:
freq = image[0].header["CRVAL3"]
image[0].header["FREQ"] = freq
except KeyError:
pass
if image[0].header["NAXIS"] == 3:
image[0].data = image[0].data[0, :, :]
elif image[0].header["NAXIS"] == 4:
image[0].data = image[0].data[0, 0, :, :]
else:
pass
if strip_wcs:
try: image[0].header["FREQ"] = image[0].header["CRVAL3"]
except KeyError: pass
for i in ["3", "4"]:
for j in ["CRVAL"+i, "CTYPE"+i, "CDELT"+i, "CRPIX"+i, "NAXIS"+i, "CUNIT"+i, "CROTA"+i]:
try: del image[0].header[j]
except KeyError: pass
image[0].header["NAXIS"] = 2
if outname is None:
if not fitsimage.endswith(".fits"): fitsimage += ".fits"
outname = fitsimage
image.writeto(outname, clobber=True)
if opened:
image.close()
def find_freq(hdr):
"""
"""
freq = None
if "FREQ" in hdr.keys():
freq = hdr["FREQ"]
if "CRVAL3" in hdr.keys() and freq is None:
if "FREQ" in hdr["CTYPE3"]:
freq = hdr["CRVAL3"]
if "CRVAL4" in hdr.keys() and freq is None:
if "FREQ" in hdr["CTYPE4"]:
freq = hdr["CRVAL4"]
if "CENTCHAN" in hdr.keys() and freq is None:
# specific to MWA data
freq = float(hdr["CENTCHAN"]) * 1.28e6
return freq
def read_fits(fitsimage):
"""Read a FITS file with astropy.io.fits and return relevant data.
Because the FITS standard is in fact not completely standard there are
a few little things that need to be checked to look for the necessary
header data.
"""
opened = False
if isinstance(fitsimage, str):
# if not fitsimage.endswith(".fits"): fitsimage += ".fits"
hdulist = fits.open(fitsimage)
opened = True
elif isinstance(fitsimage, fits.HDUList):
hdulist = fitsimage
else:
raise IOError(">>> Specified FITS image must an astropy.io.fits.HDUList" \
"object or a filepath.")
harray = hdulist[0].header
farray = np.squeeze(hdulist[0].data)
naxis = harray["NAXIS"]
if ("NAXIS3" in harray.keys()) and naxis == 2:
for k in ["NAXIS", "CDELT", "CRVAL", "CTYPE", "CRPIX"]:
del harray[k+"3"]
if ("NAXIS4" in harray.keys()) and naxis < 4:
for k in ["NAXIS", "CDELT", "CRVAL", "CTYPE", "CRPIX"]:
del harray[k+"4"]
warray = WCS(harray).celestial
if opened: hdulist.close()
# Read some things from the FITS header and check some things:
# try: farray.shape = (harray["NAXIS2"], harray["NAXIS1"])
# except ValueError: raise ValueError(">>> FITS files must be flat.")
# Try to find pixel sizes:
try:
cd1, cd2 = harray["CDELT1"], harray["CDELT2"]
except KeyError:
try:
cd1, cd2 = harray["CD1_1"], harray["CD2_2"]
except KeyError:
raise KeyError(">>> Cannot find key for pixel sizes.")
# Beam parameters:
semi_a, semi_b, beam_area, beam_not_found = None, None, None, True
if ("BMAJ" in harray.keys()) and ("BMIN" in harray.keys()):
semi_a = 0.5 * harray["BMAJ"] # Normal keys.
semi_b = 0.5 * harray["BMIN"]
beam_not_found = False
elif ("CLEANBMJ" in harray.keys()) and ("CLEANBMN" in harray.keys()):
semi_a = 0.5 * harray["CLEANBMJ"] # Abnormal keys, e.g. VLSSr.
semi_b = 0.5 * harray["CLEANBMN"]
beam_not_found = False
else:
try: # Check for NVSS:
for i in range(len(harray["HISTORY"])):
if "'NRAO VLA SKY SURVEY" in harray["HISTORY"][i]:
semi_a = 0.5 * 1.2500e-2
semi_b = 0.5 * 1.2500e-2
beam_not_found = False
if beam_not_found: raise KeyError
except KeyError:
try: # AIPS has a tell-tale mark:
for i in range(len(harray["HISTORY"])):
if "BMAJ" in harray["HISTORY"][i]:
l = []
for t in harray["HISTORY"][i].split():
try: l.append(float(t))
except ValueError: pass
semi_a = 0.5 * l[0]
semi_b = 0.5 * l[1]
beam_not_found = False
if beam_not_found: raise KeyError
except (KeyError, IndexError):
try: # Check for SUMSS, which does NOT have the beam information.
# We will use the declination-dependent beam size based on
# the reference pixel of the FITS file.
for i in range(len(harray["HISTORY"])):
if "sumss" in harray["HISTORY"][i].lower():
decl = math.radians(abs(harray["CRVAL2"]))
# beam_area = 0.25 * np.pi * (45.0**2 / 3600.0**2) * \
# (1.0 / math.sin(decl))
semi_a = 0.5 * (45./3600.)
semi_b = 0.5 * (45./(3600. * math.sin(decl)))
beam_not_found = False
if beam_not_found: raise KeyError
except KeyError:
raise KeyError(">>> Beam parameters not found. {}".format(fitsimage))
if beam_area is None:
beam_area = np.pi * semi_a * semi_b
bpp = beam_area / (abs(cd1*cd2) * np.log(2.0))
beam = (semi_a*2., semi_b*2.)
beam_major = semi_a*2.
beam_minor = semi_b*2.
# include abs() for beam params as sometimes these can be negative...
return np.squeeze(farray), warray, abs(bpp), cd1, cd2, naxis, abs(beam_major), abs(beam_minor)
def get_header(fitsimage):
"""
"""
opened = False
if isinstance(fitsimage, str):
# if not fitsimage.endswith(".fits"): fitsimage += ".fits"
hdulist = fits.open(fitsimage)
opened = True
elif isinstance(fitsimage, fits.HDUList):
hdulist = fitsimage
else:
raise IOError(">>> Specified FITS image must an astropy.io.fits.HDUList" \
"object or a filepath.")
harray = hdulist[0].header
return harray
def write_fits_table(outname, names, *params):
"""
"""
columns_to_add = []
for i, data in enumerate(params):
if names[i] == "name":
fformat = "A"
else:
fformat = "E"
columns_to_add += [
fits.Column(name=names[i], format=fformat,
array=data)
]
if not outname.lower().endswith(".fits"):
outname += ".fits"
hdu = fits.BinTableHDU.from_columns(columns_to_add)
hdu.writeto(outname, overwrite=True)
def get_bpp(bmaj, bmin, cd1, cd2):
return (np.pi*bmaj*bmin) / (4.*abs(cd1*cd2)*np.log(2.))
def rms_array(rms, farray=None):
"""Load or generate rms array.
"""
if farray is not None:
farray = np.squeeze(farray)
try:
rms = float(rms)
rarray = None
except (TypeError, ValueError):
if isinstance(rms, str): rarray = fits.getdata(rms)
elif isinstance(rms, fits.HDUList): rarray = rms[0].data
else: raise ValueError(">>> RMS must be specified as either a single " \
"value or as an array/filepath.")
if rarray is None:
if farray is None:
raise ValueError(">>> If RMS array is to be made a template array" \
" must be specified")
else:
rarray = np.full_like(farray, rms)
rarray = np.squeeze(rarray)
if rarray.shape != farray.shape:
print(farray.shape, rarray.shape)
raise ValueError(">>> RMS array and image array must be the same size.")
return np.squeeze(rarray)
def psf_array(psf, farray=None, index=0):
"""
"""
try:
psf = float(psf)
parray = None
except (TypeError, ValueError):
if isinstance(psf, str):
parray = fits.getdata(psf)[index, ...]
elif isinstance(psf, fits.HDUList):
parray = psf[0].data[index, ...]
else:
raise ValueError(">>> PSF must be specified as either a single "
"value or a as an array/filepath.")
if parray is None:
if farray is None:
raise ValueError(">>> If PSF array is to be made a template array "
"must be specified.")
else:
parray = np.full_like(farray, psf)
parray = np.squeeze(parray)
if parray.shape != farray.shape:
raise ValueError(">>> PSF array and image array must be the same size.")
return parray
# def pixscale_array(cd, farray=None, index=0)
def blank_fits_diff(image, ref, outname, rms, sigma=3., overwrite=False):
"""Blank image based on ref where ref >= rms*sigma.
rms can be image or single value as in other tasks.
"""
farray, warray, _, _, _, naxis = read_fits(ref)
rarray = rms_array(rms, farray)
strip_naxis(image, outname=image[:-5]+"_stripped.fits")
im = fits.open(image[:-5]+"_stripped.fits")
wm = WCS(im[0].header)
if naxis > 2:
raise ValueError("NAXIS must be <= 2.")
ref_ra, ref_dec, ref_x, ref_y = [], [], [], []
for i in range(farray.shape[0]):
for j in range(farray.shape[1]):
r, d = pix_to_world(i, j, warray)
ref_ra.append(r)
ref_dec.append(d)
ref_x.append(i)
ref_y.append(j)
ref_c = SkyCoord(ref_ra, ref_dec, unit=(u.deg, u.deg))
im_ra, im_dec, im_x, im_y = [], [], [], []
for i in range(im[0].data.shape[0]):
for j in range(im[0].data.shape[1]):
if not np.isnan(im[0].data[i, j]):
r, d = pix_to_world(i, j, wm)
c = SkyCoord(r, d, unit=(u.deg, u.deg))
index = c.match_to_catalog_sky(ref_c)[0]
x, y = ref_x[index], ref_y[index]
if farray[x, y] < sigma*rarray[x, y]:
im[0].data[i, j] = np.nan
im.writeto(outname, clobber=overwrite)
class Tree():
"""Grow a tree with branches and leaves.
Grow a source from neighbouring pixels.
"""
def __init__(self, tree_number, threshold):
""" 'The seed of a tree of giants.' """
self.no = tree_number # The source ID.
self.th = threshold[0] # Threshold above rms needed for detection.
self.gh = threshold[1] # Threshold above rms needed for growing the detection.
self.mh = threshold[2] # maximum threshold above rms
def seedling(self, m, n, farray, warray, rarray, forest, diagonals, barray):
"""Start from a seedling and grow a tree."""
if farray[m, n] >= self.th*rarray[m, n]: # Detection!
forest[m, n] = self.no # Set ref to ID
self.leaves = 1 # Count pixels
self.fluxes = np.array([farray[m, n]]) # Add flux
self.coords = np.array([(m, n)]) # Add pixel coordinates
self.bounds = np.array([(m, n)]) # Boundary coordinates
self.bright = farray[m, n] # Brightest pixel
self.bcoord = [(m, n)] # BP coordinates
self.rluxes = np.array([rarray[m, n]]) # Add rmses
self.bpp = np.array([barray[m, n]])
indices = [(m, n)] # Indices to check. This is added to.
for i, j in indices:
# Surrounding pixels:
if diagonals:
surrounding_indices = [(i-1, j-1), (i-1, j), (i, j-1), \
(i+1, j-1), (i-1, j+1), (i+1, j), (i, j+1), (i+1, j+1)]
else:
surrounding_indices = [(i-1, j), (i, j-1), (i+1, j), \
(i, j+1)]
if i == m and j == n: boundary = True
else: boundary = False
for index in surrounding_indices:
if (index[0] < 0) or (index[1] < 0):
pass
else:
try:
if np.isnan(forest[index]) and \
(farray[index] >= self.gh*rarray[index]) and \
(farray[index] < self.mh*rarray[index]):
self.leaves += 1
self.fluxes = np.append(self.fluxes, \
farray[index])
self.bpp = np.append(self.bpp, barray[index])
self.rluxes = np.append(self.rluxes, \
rarray[index])
self.coords = np.append(self.coords, [index], \
axis=0)
forest[index] = self.no
if farray[index] > self.bright:
self.bright = farray[index]
self.bcoord = [index]
indices.append(index)
elif np.isnan(forest[index]) and \
(farray[index] < self.gh*rarray[index]) or \
(farray[index] >= self.mh*rarray[index]):
forest[index] = 0
farray[index] = np.nan
if not boundary:
self.bounds = np.append(self.bounds, \
[(i, j)], axis=0)
boundary = True
elif forest[index] == 0:
if not boundary:
self.bounds = np.append(self.bounds, \
[(i, j)], axis=0)
boundary = True
pass
except IndexError:
pass
tree_number = self.no + 1
else:
tree_number = self.no
forest[m, n] = 0
farray[m, n] = np.nan
return farray, forest, tree_number
def populate_forest(farray, warray, rarray, threshold, max_pix, min_pix, \
diagonals, barray):
"""Grow trees in a forest; find sources in a field."""
# An empty forest:
forest = np.empty((len(farray[:, 0]), len(farray[0, :])))
forest[:] = np.nan
tree_number = 1 # The current source ID,
tree_leaves = {tree_number: 0} # its pixels,
tree_fluxes = {tree_number: 0} # its flux values,
tree_coords = {tree_number: 0} # its pixel coordinates,
tree_bounds = {tree_number: 0} # its boundary coordinates,
tree_bright = {tree_number: 0} # Source brightest pixel coordinates.
tree_height = {tree_number: 0}
tree_rms = {tree_number: 0} # Sum of rms.
tree_bpp = {tree_number: 0}
for n in range(0, len(farray[0, :])):
sys.stdout.write(u"\u001b[1000D" + "{:.>6.1f}%".format(100.*n/len(farray[0, :])))
sys.stdout.flush()
for m in range(0, len(farray[:, 0])):
# If forest[m, n] is not NaN, it has already been checked.
if np.isnan(forest[m, n]):
t = Tree(tree_number, threshold)
farray, forest, tree_number = t.seedling(m, n, farray, \
warray, rarray, forest, diagonals, barray)
try:
if (min_pix <= t.leaves <= max_pix):
tree_leaves[tree_number-1] = t.leaves
tree_fluxes[tree_number-1] = t.fluxes
tree_coords[tree_number-1] = t.coords
tree_bounds[tree_number-1] = t.bounds
tree_bright[tree_number-1] = t.bcoord
tree_height[tree_number-1] = t.bright
tree_rms[tree_number-1] = t.rluxes
tree_bpp[tree_number-1] = t.bpp
else:
pass
except AttributeError:
pass
print("")
return farray, forest, tree_leaves, tree_fluxes, tree_coords, tree_bounds, \
tree_bright, tree_height, tree_rms, tree_bpp
def measure_forest(fitsimage, rms=None, cutoff1=None, \
cutoff2=None, cutoff3=None, max_pix=500, min_pix=2, diagonals=True, \
LAS=True, annfile=None, outfile=None, outimage=None, \
verbose=True,
psf=None,
offset_correct=False,
threshold1=None,
threshold2=None):
"""Calculate the fluxes of individual sources within a FITS file.
Parameters
----------
fitsimage : str or HDUList object
Either the path to a FITS file or the HDUList object if already
opened.
rms : float or str
Either a single rms value for the image, or a rms image mirroring
the input FITS file. Minimum detection threshold is `rms` * `cutoff`
for each pixel.
cutoff1 : int, optional
The multiple of `rms` needed for a detection. Default is 3sigma.
cutoff2 : int, optional
The multiple of `rms` needed for growing sources. Default is `cutoff1`.
max_pix : int, optional
Maximum number of pixels in a detection. Useful only to save
time ignoring large sources (e.g., Fornax A) as LAS calculations
are ridiculously slow.
min_pix : int, optional
Minimum number of pixels for a detection.
diagonals : bool, optional
Specifies whether source detection counts pixels only connected
diagonally. Select True for diagonal detection.
LAS : bool, optional
Select True is wanting to calculate the largest angular size of
each source. THIS IS VERY SLOW.
annfile : str, optional
File to write annotations to. This creates a new file or over-
writes an existing one.
outfile : str, optional
File to write out results to. This creates a new file or over-
writes an existing one.
outimage : str, optional
This allows writing a FITS file with the same header/size as
the input image but with pixels below the detection/growth
thresholds blanked. An exisiting file with this name will
be deleted.
verbose : bool, optional
Select True if wanting to print output to terminal.
"""
ann_opened = False
if outfile is not None: start_time = datetime.now()
# --------------------------------------------------------------------------
if annfile is not None:
if annfile.endswith("ann") or annfile.endswith("reg"):
ann = open(annfile, "w+")
ann_opened = True
else:
logging.warn(">>> Annotation file must be for Kvis (.ann) or " \
" DS9 (.reg).")
logging.warn(">>> No annotation file will be made.")
# --------------------------------------------------------------------------
if threshold1 is not None:
cutoff1 = threshold1
else:
if cutoff1 is None: cutoff1 = 3
if threshold2 is not None:
cutoff2 = threshold2
else:
if cutoff2 is None: cutoff2 = cutoff1
if cutoff3 is None: cutoff3 = 1.e9
logging.info(">>> Detection threshold set to {0} sigma.".format(cutoff1))
logging.info(">>> Growth threshold set to ...{0} sigma.".format(cutoff2))
farray, warray, bpp, cd1, cd2, naxis, beam_major, beam_minor = read_fits(fitsimage)
rarray = rms_array(rms, farray)
if psf is None:
logging.info(">>> using PSF {:.2f}\" times {:.2f}\"".format(beam_major*3600.,
beam_minor*3600.))
bmaj = psf_array(beam_major, farray)
bmin = psf_array(beam_minor, farray)
else:
logging.info(">>> using PSF map from {}".format(psf))
bmaj = psf_array(psf, farray, 0)
bmin = psf_array(psf, farray, 1)
bpp_array = get_bpp(bmaj, bmin, cd1, cd2)
if rarray.shape != farray.shape:
raise ValueError(">>> RMS array {} and image array {} must be the same size.".format(
rarray.shape, farray.shape))
farray, forest, tree_leaves, tree_fluxes, tree_coords, tree_bounds,\
tree_bright, tree_height, tree_rms, tree_bpp = populate_forest(
farray=farray, \
warray=warray, rarray=rarray, threshold=(cutoff1, cutoff2, cutoff3), \
max_pix=max_pix, min_pix=min_pix, diagonals=diagonals,
barray=bpp_array)
if (len(tree_leaves) == 1) and (tree_leaves[1] == 0):
raise RuntimeError(">>> No sources detected for {0} with threshold = "\
"{1} sigma.".format(fitsimage, cutoff1))
zero_flag = False
if tree_leaves[1] == 0:
zero_flag = True
del tree_leaves[1]
del tree_fluxes[1]
del tree_coords[1]
del tree_bounds[1]
del tree_bright[1]
del tree_height[1]
source_flux = []
source_dflux = []
source_peak = []
source_centroid = []
source_avg_flux = []
source_avg_rms = []
source_bcoord = []
source_area = []
source_npix = []
source_LAS = []
source = []
source_boundaries = []
source_sum = []
if offset_correct:
hdr = get_header(fitsimage)
if "BIASA" in hdr.keys() and "BIASB" in hdr.keys():
logging.info("BIASA: {}, BIASB: {}".format(hdr["BIASA"], hdr["BIASB"]))
else:
logging.warning("No BIASA and/or BIASB parameters for offset corrections.")
offset_correct = False
for tree in tree_leaves:
if not np.isfinite(tree):
continue
flux_i = sum(tree_fluxes[tree] / tree_bpp[tree])
peak_i = tree_height[tree]
rms_i = sum(tree_rms[tree]) / tree_leaves[tree]
if offset_correct:
peak_bias = (peak_i/rms_i)*hdr["BIASA"] + hdr["BIASB"]
int_bias = (peak_bias / peak_i)*flux_i
flux_i += int_bias
source_sum.append(np.nansum(tree_fluxes[tree]))
source_flux.append(flux_i)
source_dflux.append(rms_i * np.sqrt(np.nanmean(tree_bpp[tree]) /
float(tree_leaves[tree])))
source_avg_flux.append(sum(tree_fluxes[tree]) / tree_leaves[tree])
source_avg_rms.append(rms_i)
source_area.append(abs(cd1*cd2) * tree_leaves[tree])
source_npix.append(tree_leaves[tree])
source_peak.append(peak_i)
source_bcoord.append((tree_bright[tree][0][1], tree_bright[tree][0][0]))
fx, fy = [], []
fz = sum(tree_fluxes[tree])
for i in range(len(tree_fluxes[tree])):
fx.append(tree_coords[tree][i][0] * tree_fluxes[tree][i])
fy.append(tree_coords[tree][i][1] * tree_fluxes[tree][i])
source_centroid.append((sum(fx) / fz, sum(fy) / fz))
# The largest angular scale of the source.
# This is simply calculated as the largest angular separation between
# any two pixels that comprise the source.
if LAS:
length = 0
for pc1 in range(len(tree_bounds[tree])):
ra1, dec1 = pix_to_world(tree_bounds[tree][pc1][1], \
tree_bounds[tree][pc1][0], \
warray)
for pc2 in range(pc1+1, len(tree_bounds[tree])):
ra2, dec2 = pix_to_world(tree_bounds[tree][pc2][1], \
tree_bounds[tree][pc2][0], \
warray)
if (ra1 == ra2) and (dec1 == dec2):
diff = 0.0
else:
diff = angular_distance((ra1, dec1), (ra2, dec2))
if diff > length:
length = diff
source_LAS.append(length)
else:
source_LAS.append(np.nan)
# ----------------------------------------------------------------------
if ann_opened:
ord_coord = order_boundaries(tree_bounds[tree])
if annfile.endswith("ann"):
ann.write("COLOR RED\nCOORD W\n")
ann.write("CLINES ")
elif annfile.endswith("reg"):
ann.write("global color=yellow\nfk5\n")
ann.write("polygon ")
for i in range(len(ord_coord)):
r_dd, d_dd = pix_to_world(ord_coord[i][0], \
ord_coord[i][1], warray)
ann.write("{0} {1} ".format(r_dd, d_dd))
ann.write("\n")
# ----------------------------------------------------------------------
if zero_flag: source.append(tree-1)
else: source.append(tree)
wx, wy, bx, by = [], [], [], []
for i in range(len(source)):
wx.append(source_centroid[i][0])
wy.append(source_centroid[i][1])
bx.append(source_bcoord[i][0])
by.append(source_bcoord[i][1])
world_coords = pix_to_world(wx, wy, warray)
bright_coords = pix_to_world(bx, by, warray)
if outfile is not None:
if outfile.lower().endswith(".fits"):
source_ra = [world_coords[0][i] for i in range(len(source))]
source_dec = [world_coords[1][i] for i in range(len(source))]
bright_ra = [bright_coords[0][i] for i in range(len(source))]
bright_dec = [bright_coords[1][i] for i in range(len(source))]
names = ["source", "int_flux", "err_int_flux", "avg_flux",
"local_rms", "area", "npix", "ra", "dec", "pra", "pdec",
"las", "peak_flux", "sum"]
write_fits_table(outfile, names, source, source_flux, source_dflux,
source_avg_flux, source_avg_rms, source_area, source_npix,
source_ra, source_dec, bright_ra, bright_dec,
source_LAS, source_peak, source_sum)
else:
if outfile[-3:] == "csv":
de = ","
else: de = " "
with open(outfile, "w+") as f:
# f.write(" # Sources and their parameters found by `measure_forest`:\n"\
# " #\n" \
# " # ............ Input FITS = {0}\n" \
# " # ................ Output = {1}\n" \
# " # .... Detection treshold = {2}\n" \
# " # ...... Growth threshold = {3}\n" \
# " # ........ Minimum pixels = {4}\n" \
# " # ........ Maximum pixels = {5}\n" \
# " # Total number of sources = {6}\n" \
# " # ............ Time taken = {7}\n" \
# " # ................... LAS = {8}\n" \
# " # \n" \
# " # source{9}flux{9}dflux{9}avg_flux{9}avg_rms{9}area{9}npix{9}centroid_RA{9}centroid_DEC{9}bright_RA{9}bright_DEC{9}LAS{9}peak{9}sum\n" \
# " # Jy Jy Jy/Beam deg^2 Jy/Beam deg deg deg deg deg Jy/beam Jy/beam\n" \
# " # 0 1 2 3 4 5 6 7 8 9 10 11 12 13\n" \
# .format(fitsimage, outfile, cutoff1, cutoff2, min_pix, \
# max_pix, len(source), datetime.now()-start_time, LAS, de))
f.write("source{0}flux{0}dflux{0}avg_flux{0}avg_rms{0}area{0}npix{0}centroid_RA{0}centroid_DEC{0}bright_RA{0}bright_DEC{0}LAS{0}peak{0}sum\n".format(de))
for i in range(len(source)):
f.write("{0}{11}{1}{11}{2}{11}{3}{11}{4}{11}{5}{11}{6}{11}{7}" \
"{11}{8}{11}{9}{11}{10}{11}{12}{11}{13}{11}{14}\n".format(source[i], \
source_flux[i], source_dflux[i], source_avg_flux[i], \
source_avg_rms[i], source_area[i], source_npix[i], \
world_coords[0][i], world_coords[1][i], \
bright_coords[0][i], bright_coords[1][i], de, \
source_LAS[i], source_peak[i], source_sum[i]))
# --------------------------------------------------------------------------
if ann_opened:
if annfile.endswith("reg"):
for i in range(len(source)):
ann.write(r"text {0} {1} {{0}}\\n".format(\
world_coords[0][i], world_coords[1][i], \
source[i]))
elif annfile.endswith("ann"):
for i in range(len(source)):
ann.write("TEXT {0} {1} {2}\n".format( \
world_coords[0][i], world_coords[1][i], \
source[i]))
ann.close()
# --------------------------------------------------------------------------
if outimage is not None:
if isinstance(fitsimage, str):
hdulist = fits.open(fitsimage)
elif isinstance(fitsimage, fits.HDUList):
hdulist = fitsimage
hdulist[0].data = farray
if os.path.exists(outimage):
logging.warn(">>> Deleting old {0}...".format(outimage))
os.remove(outimage)
hdulist[0].header["HISTORY"] = "Output image from `fluxtools.py`."
hdulist.writeto(outimage)
hdulist.close()
if len(source) == 1:
world_coords, bright_coords = ([world_coords[0]], [world_coords[1]]), \
([bright_coords[0]], [bright_coords[1]])
return np.array([source, source_flux, source_dflux, source_avg_flux, source_avg_rms, source_area, \
source_npix, world_coords[0], world_coords[1], bright_coords[0], bright_coords[1],
source_LAS, source_peak, source_sum]).T
def measure_tree(fitsimage, coords, rms, cutoff1=3, cutoff2=None, max_pix=500, \
min_pix=2, max_sep=1.0, diagonals=True, LAS=True, annfile=None, \
outfile=None, \
outimage=None, verbose=False,
use_existing=None,
psf=None,
offset_correct=False,
threshold1=None,
threshold2=None,):
"""Calculate the fluxes of an individual.
Parameters
----------
fitsimage : str or HDUList object
Either the path to a FITS file or the HDUList object if already
opened.
coords : tuple of floats
Coordinates of source of interest. Should be in decimal degrees.
rms : float or str
Either a single rms value for the image, or a rms image mirroring
the input FITS file. Minimum detection threshold is `rms` * `cutoff`
for each pixel.
cutoff1 : int, optional
The multiple of `rms` needed for a detection. Default is 3sigma.
cutoff2 : int, optional
The multiple of `rms` needed for growing sources. Default is `cutoff1`.
max_pix : int, optional
Maximum number of pixels in a detection. Useful only to save
time ignoring large sources (e.g., Fornax A) as LAS calculations
are ridiculously slow.
min_pix : int, optional
Minimum number of pixels for a detection.
diagonals : bool, optional
Specifies whether source detection counts pixels only connected
diagonally. Select True for diagonal detection.
LAS : bool, optional
Select True is wanting to calculate the largest angular size of
each source. THIS IS VERY SLOW.
annfile : str, optional
File to write annotations to. This creates a new file or over-
writes an existing one.
outfile : str, optional
File to write out results to. This creates a new file or over-
writes an existing one.
outimage : str, optional
This allows writing a FITS file with the same header/size as
the input image but with pixels below the detection/growth
thresholds blanked. An exisiting file with this name will
be deleted.
verbose : bool, optional
Select True if wanting to print output to terminal.
"""
params = None
if use_existing is not None:
if os.path.exists(use_existing):
if use_existing.endswith(".csv"):
params = np.genfromtxt(use_existing, delimiter=",", skip_header=1)
if params is None:
# A forest in which our tree resides:
params = measure_forest(fitsimage=fitsimage,
rms=rms,
cutoff1=cutoff1,
cutoff2=cutoff2,
max_pix=max_pix,
min_pix=min_pix, \
diagonals=diagonals,
LAS=LAS,
annfile=annfile,
outfile=outfile,
outimage=outimage,
verbose=verbose,
psf=psf,
offset_correct=offset_correct,
threshold1=threshold1,
threshold2=threshold2)
source = params[:, 0]
source_flux = params[:, 1]
source_dflux = params[:, 2]
source_avg_flux = params[:, 3]
source_avg_rms = params[:, 4]
source_area = params[:, 5]
source_npix = params[:, 6]
world_coords_ra = params[:, 7]
world_coords_dec = params[:, 8]
bright_coords_ra = params[:, 9]
bright_coords_dec = params[:, 10]
source_LAS = params[:, 11]
source_peak = params[:, 12]
# source, source_flux, source_dflux, source_avg_flux, source_avg_rms, source_area, \
# source_npix, world_coords_ra, world_coords_dec, bright_coords_ra, bright_coords_dec, \
# source_LAS, source_peak = \
world_coords = (world_coords_ra, world_coords_dec)
bright_coords = (bright_coords_ra, bright_coords_dec)
# Now to find the tree:
c = SkyCoord(coords[0], coords[1], unit=(u.deg, u.deg))
ww_catalogue = SkyCoord(world_coords[0], world_coords[1], unit=(u.deg, u.deg))
if len(source) != 1:
i = c.match_to_catalog_sky(ww_catalogue)[0]
else:
i = 0
dist = angular_distance((coords[0], coords[1]), \
(world_coords[0][i], world_coords[1][i]))
if dist > max_sep:
raise RuntimeError("No sources found within `max_sep`.")
if verbose:
if dist < 1.0:
dist_print = dist * 60.0
dist_unit = "arcmin"
if dist_print < 1.0:
dist_print *= 60.0
dist_unit = "arcsec"
else:
dist_print = dist
dist_unit = "deg"
print(">>> The following parameters have been found:\n" \
".............. Source no. = {11}\n" \
"............... Int. flux = {0} [Jy]\n" \
"......... Error int. flux = {1} [Jy]\n" \
"............... Peak flux = {2} [Jy/beam]\n" \
"............... Avg. flux = {3} [Jy/beam]\n" \
".............. No. pixels = {4}\n" \
"Flux weighted coordinates = ({5}, {6})\n" \
"..................... LAS = {7} [deg]\n" \
"............. Source area = {8} [deg^2]\n" \
"....... Offset from input = {9} [{10}]".format(\
source_flux[i], source_dflux[i], source_peak[i], \
source_avg_flux[i], source_npix[i], world_coords[0][i], \
world_coords[1][i], source_LAS[i], source_area[i], dist_print, \
dist_unit, source[i]))
return source[i], source_flux[i], source_dflux[i], source_peak[i], \
source_avg_flux[i], source_npix[i], (world_coords[0][i], \
world_coords[1][i]), source_LAS[i], \
source_area[i], (bright_coords[0][i], bright_coords[1][i])
#
def measure_aperture(fitsimage, coords, radius, rms=None, sigma=3, LAS=False, \
verbose=True, radius_units="deg", z=0, psf=None,
offset_correct=True, absolute_flux=False,
writeout_image=False,
blob_correct=False,
):
"""Measure flux within a circular aperture.
Parameters
----------
fitsfimage : string or astropy.io.fits.HDUList
If string this should be the filename and path to a FITS file.
RA : float
Central RA in decimal degrees.
DEC : float
Central DEC in decimal degrees.
radius : float
Aperture within which to calculate flux in degree.
rms : float or str
Either a single rms value for the image, or a rms image mirroring
the input FITS file. Minimum detection threshold is `rms` * `cutoff`
cutoff : int, optional
Multiple of the RMS required for detection. Default is 3.
LAS : bool, optional
If True an LAS is calculated.
verbose : bool, optional
If True results are printed to the terminal.
radius_units : {'deg', 'arcmin', 'arcsec'}, optional
Specifies the unit for `radius`.
"""
if verbose:
print(">>> running measure_aperture on {} with rms {}".format(fitsimage, rms))
farray, warray, bpp, cd1, cd2, naxis, beam_major, beam_minor = read_fits(fitsimage)
if rms is not None:
rarray = rms_array(rms, farray)
rarray = np.squeeze(rarray)
if psf is None:
if verbose:
logging.info(">>> using PSF {:.2f}\" times {:.2f}\"".format(beam_major*3600.,
beam_minor*3600.))
bmaj = psf_array(beam_major, farray)
bmin = psf_array(beam_minor, farray)
else:
if verbose:
logging.info(">>> using PSF map from {}".format(psf))
bmaj = psf_array(psf, farray, 0)
bmin = psf_array(psf, farray, 1)
# set pixel scaling so we can strip projection-related effects?
bpp_array = get_bpp(bmaj, bmin, cd1, cd2)
farray = np.squeeze(farray)
r = (radius * units[radius_units]).to(u.degree).value
scale = int((r / abs(cd1)) + 10)
yr, xr = warray.celestial.all_world2pix(coords[0], coords[1], 0)
yr = int(yr)
xr = int(xr)
if absolute_flux:
farray = np.absolute(farray)
source_flux, source_rms, source_xpixel, source_ypixel, source_coords = \
[], [], [], [], []
source_bpp = []
source_peak = 0
x_range = [xr-scale, xr+scale]
y_range = [yr-scale, yr+scale]
scale_pix = scale - 10
dist = norm_method(farray, (xr, yr))
cond1 = dist <= scale_pix
if rms is not None:
cond2 = farray >= sigma*rarray
else:
cond2 = True
indices = np.where(cond1 & cond2)
indices2 = np.where(~cond1 | ~cond2)
if writeout_image:
farray[indices2] = np.nan
fits.writeto(fitsimage.replace(".fits", "_ww.fits"),
farray,
fits.getheader(fitsimage),
overwrite=True)
source_flux = farray[indices].flatten()
source_bpp = bpp_array[indices].flatten()
if rms is not None:
source_rms = rarray[indices].flatten()
source_xpixel = indices[0].flatten()
source_ypixel = indices[1].flatten()
source_peak = np.nanmax(source_flux)
int_flux = sum(source_flux / source_bpp)
if rms is not None:
unc_flux = (sum(source_rms / source_bpp) *
np.sqrt(np.nanmean(source_bpp) / float(len(source_rms))))
else:
unc_flux = 0.0
area = len(source_flux) * abs(cd1*cd2)
npix = len(source_flux)
on_source_rms = np.sqrt((np.mean(np.asarray(source_flux)**2)))
rms = np.mean(source_rms)
if offset_correct:
hdr = get_header(fitsimage)
if "BIASA" in hdr.keys() and "BIASB" in hdr.keys():
peak_bias = (source_peak/rms)*hdr["BIASA"] + hdr["BIASB"]
# peak_bias = hdr["BIASB"]
logging.info("peak bias: {} Jy/beam".format(peak_bias))
int_bias = (peak_bias / source_peak)*int_flux
logging.info("integrated flux density bias: {} Jy".format(int_bias))
int_flux += int_bias
LAS = False # none of this crap
if LAS:
las = 0
for i in range(len(source_coords)):
for j in range(len(source_coords)):
if angular_distance(source_coords[i], source_coords[j]) > las:
las = angular_distance(source_coords[i], source_coords[j])
else:
las = "NA"
if blob_correct:
# https://doi.org/10.1111/j.1365-2966.2012.21373.x
snr = source_peak / rms
eta = (erf(np.sqrt(-np.log((sigma / snr)))))**2
print(">>> eta = {}".format(eta))
print(">>> flux from {} to {}".format(int_flux, int_flux/eta))
int_flux /= eta
if verbose:
print(">>> The following parameters have been found:\n" \
"............... Int. flux = {0} [Jy]\n" \
"......... Error int. flux = {1} [Jy]\n" \
"............... Peak flux = {2} [Jy/beam]\n" \
".............. No. pixels = {3}\n" \
"..................... LAS = {4} [deg]\n" \
"............. Source area = {5} [deg^2]\n" \
"........... On source rms = {7} [Jy/beam]\n" \
"..................... rms = {6} [Jy/beam]".format(\
int_flux, unc_flux, source_peak, npix, las, area, rms, on_source_rms))
if np.isnan(unc_flux):
unc_flux = 0.
return int_flux, unc_flux, source_peak, npix, las, area, rms
def measure_region(fitsimage, rms, region, r_index=0, sigma=3, annfile=None, \
annfile_color="yellow", verbose=True, pix_buff="A",
psf=None, offset_correct=True,
absolute_flux=False,
clean_bias_factor=1.,
clean_bias_std=0.,
model_map=None,
residual_map=None,
dOmega_map=None,
full_region_error=False,
blob_correct=False):
"""Measure integrated flux within polygon region.
Requires pyregion if using ds9 region file. Inspired by `radioflux.py` by
Martin Hardcastle: https://github.com/mhardcastle/radioflux, but I wanted a bit
more control over errors and additional MWA-specific corrections.
This adapts a C++ implementation found here:
http://www.geeksforgeeks.org/how-to-check-if-a-given-point-lies-inside-a-polygon/
Note that region vertices must be ordered.
Parameters
----------
fitsfimage : string or astropy.io.fits.HDUList
If string this should be the filename and path to a FITS file.
rms : float or str
Either a single rms value for the image, or a rms image mirroring
the input FITS file. Minimum detection threshold is `rms` * `cutoff`
region : str, list, or np.ndarray
If a string, this should be a filepath to a ds9.reg file. If
a list or array, these should be ordered vertices of a polygon
in world coordinates of the image.
r_index : int, optional
Specifies the index of the polygon if using a ds9.reg file.
sigma : int, optional
Multiple of the RMS required for measurement. Default is 3.
annfile : str, optional
File to write annotations to. This creates a new file or over-
writes an existing one. The annotations here are just dots
indicating each pixel that is measured.
annfile_color: str, optional
Color of the annotations. Default is `yellow`.
verbose : bool, optional
If True, additional output is printed to the terminal.
"""
def is_in(x, y, region_x, region_y, max_x):
"""Check if (x, y) is in region.
(x, y) is considered in region if the followed is met:
A line drawn horizontally to the right from (x, y) intersects
with an odd number of region edges.
"""
def orientation(p1, p2, p3):
"""Get orientation of ordered triplet.
0 == collinear
1 == clockwise
2 == counter-clockwise
"""
slope = (p2[1] - p1[1]) * (p3[0] - p2[0]) - \
(p3[1] - p2[1]) * (p2[0] - p1[0])
if slope < 0:
orient = 2
elif slope > 0:
orient = 1
else:
orient = 0
return orient
def on_segment(p1, p2, p3):
"""Checks if p3 lies on segment (p1, p2)."""
if ((p3[0] <= max(p1[0], p2[0])) and (p3[0] >= min(p1[0], p2[0])) and\
(p3[2] <= max(p1[1], p2[1])) and (p3[1] >= min(p1[1], p2[1]))):
return True
else:
return False
def intersects(p1, q1, p2, q2):
"""Determine if line segment (p1, q1) intersects with (p2, q2)
Uses orientation conditions.
"""
inter = False
# General case:
if (orientation(p1, q1, p2) != orientation(p1, q1, q2)) and \
(orientation(p2, q2, p1) != orientation(p2, q2, q1)):
inter = True
# Special cases:
if (orientation(p1, q1, p2) == 0) and (on_segment(p1, q1, p2)):
inter = True
if (orientation(p1, q1, q2) == 0) and (on_segment(p1, q1, q2)):
inter = True
if (orientation(p2, q2, p1) == 0) and (on_segment(p2, q2, p1)):
inter = True
if (orientation(p2, q2, q1) == 0) and (on_segment(p2, q2, q1)):
inter = True
return inter
coords_in_region = []
for i in range(len(x)):
p1, q1 = (x[i], y[i]), (x[i]+max_x, y[i])
intersections = 0
for j in range(len(region_x)):
p2 = (region_x[j], region_y[j])
if j == len(region_x)-1:
q2 = (region_x[0], region_y[0])
else:
q2 = (region_x[j+1], region_y[j+1])
if intersects(p1, q1, p2, q2):
intersections += 1
if intersections%2 == 0:
in_region = False
else:
in_region = True
coords_in_region.append(in_region)
return coords_in_region
sigma = float(sigma)
#
ra, dec = [], []
if isinstance(region, str):
if region.endswith(".reg"):
import pyregion
r = pyregion.open(region)[r_index].coord_list
for i in range(0, len(r), 2):
ra.append(r[i])
dec.append(r[i+1])
elif region.endswith(".ann"):
poly_coords = kvis_polygon(region)
ra = [coord[0] for coord in poly_coords]
dec = [coord[1] for coord in poly_coords]
else:
raise TypeError(">>> `region` must be one of: DS9.reg, Kvis.ann, or a " \
" list of coordinate tuples.")
else:
for vertex in region:
ra.append(vertex[0])
dec.append(vertex[1])
farray, warray, bpp, cd1, cd2, naxis, beam_major, beam_minor = read_fits(fitsimage)
if rms is not None:
rarray = rms_array(rms, farray)
rarray = np.squeeze(rarray)
if psf is None:
logging.info(">>> using PSF {:.2f}\" times {:.2f}\"".format(beam_major*3600.,
beam_minor*3600.))
bmaj = psf_array(beam_major, farray)
bmin = psf_array(beam_minor, farray)
else:
logging.info(">>> using PSF map from {}".format(psf))
bmaj = psf_array(psf, farray, 0)
bmin = psf_array(psf, farray, 1)
# set pixel scaling so we can strip projection-related effects?
if model_map is not None:
model_array = np.squeeze(fits.getdata(model_map))
if dOmega_map is not None:
dOmega_array = np.squeeze(fits.getdata(dOmega_map))
else:
dOmega_array = np.ones_like(model_array)
if residual_map is not None:
residual_array = fits.getdata(residual_map)
bpp_array = get_bpp(bmaj, bmin, cd1, cd2)
max_x = len(farray[:, 0]+1)
if pix_buff in ["a", "A", "auto", "Auto", "AUTO"]:
pix_buff = int(0.1 * farray.shape[-2])
pix_r, pix_d = world_to_pix(ra, dec, warray, naxis)
min_x, max_x = min(pix_r), max(pix_r)
min_y, max_y = min(pix_d), max(pix_d)
avg_rx, avg_dy = int(np.mean(pix_r)), int(np.mean(pix_d))
x_all, y_all, f_all, r_all, b_all = [], [], [], [], []
bmaj_all, bmin_all = [], []
model_all = []
residual_all = []
dOmega_all = []
xlim1 = int(min_x-1) - pix_buff
xlim2 = int(max_x+1) + pix_buff
ylim1 = int(min_y-1) - pix_buff
ylim2 = int(max_y+1) + pix_buff
if xlim1 < 0:
xlim1 = 0
if ylim1 < 0:
ylim1 = 0
if xlim2 > len(farray[:, 0]-1):
xlim1 = len(farray[:, 0]-1)
if ylim2 > len(farray[:, 1]-1):
ylim2 = len(farray[:, 1]-1)
if absolute_flux:
farray = np.absolute(farray)
for i in range(xlim1, xlim2):
for j in range(ylim1, ylim2):
x_all.append(i)
y_all.append(j)
f_all.append(farray[i, j])
r_all.append(rarray[i, j])
b_all.append(bpp_array[i, j])
bmaj_all.append(bmaj[i, j])
bmin_all.append(bmin[i, j])
if model_map is not None:
model_all.append(model_array[i, j])
dOmega_all.append(dOmega_array[i, j])
if residual_map is not None:
residual_all.append(residual_array[i, j])
cir = is_in(x_all, y_all, pix_r, pix_d, max_x)
source_flux, source_rms, source_bpp = [], [], []
final_ra, final_dec = [], []
model_flux = []
model_dOmega = []
residual_flux = []
all_rms = []
all_bpp = []
faint_flux1, faint_rms, faint_bpp1 = [], [], []
faint_ra, faint_dec = [], []
faint_flux2, faint_bpp2 = [], []
source_bmaj, source_bmin = [], []
for i in range(len(cir)):
if cir[i] and (f_all[i] >= sigma*r_all[i]):
source_flux.append(f_all[i])
source_rms.append(r_all[i])
source_bpp.append(b_all[i])
ra_i, dec_i = pix_to_world(x_all[i], y_all[i], warray)
final_ra.append(ra_i), final_dec.append(dec_i)
source_bmaj.append(bmaj_all[i])
source_bmin.append(bmin_all[i])
# if f_all[i] < clean_sigma1*clean_threshold:
# faint_flux1.append(f_all[i])
# faint_rms.append(r_all[i])
# faint_bpp1.append(b_all[i])
# faint_ra.append(ra_i)
# faint_dec.append(dec_i)
# else:
# faint_flux2.append(f_all[i])
# faint_bpp2.append(b_all[i])
if model_map is not None:
model_flux.append(model_all[i])
model_dOmega.append(dOmega_all[i])
if residual_map is not None:
residual_flux.append(residual_all[i])
all_rms.append(r_all[i])
all_bpp.append(b_all[i])
elif cir[i]:
all_rms.append(r_all[i])
all_bpp.append(b_all[i])
print(len(all_rms))
print(len(source_rms))
if annfile is not None:
if annfile.endswith(".ann"):
with open(annfile, "w+") as g:
g.write("colour {0}\n".format(annfile_color))
for i in range(len(final_ra)):
g.write("DOT W {0} {1}\n".format(final_ra[i], final_dec[i]))
g.write("colour magenta\n")
for i in range(len(faint_ra)):
g.write("CIRCLE W {0} {1} {2}\n".format(faint_ra[i], faint_dec[i], cd2/3.))
if len(source_flux) == 0:
print("No flux above sigma*rms. No measurements done.")
return None
# raise RuntimeError(">>> No flux above sigma*rms. No measurements done.")
else:
source_flux = np.asarray(source_flux)
source_bpp = np.asarray(source_bpp)
source_rms = np.asarray(source_rms)
int_flux = sum(source_flux / source_bpp)
unc_flux = (sum(source_rms / source_bpp) *
np.sqrt(np.nanmean(source_bpp) / float(len(source_rms))))
print(">>> error on pixels above {} sigma: {} Jy".format(sigma, unc_flux))
all_rms = np.asarray(all_rms)
all_bpp = np.asarray(all_bpp)
# unc_flux = (sum(np.asarray(all_rms) / np.asarray(all_bpp) * np.sqrt(np.nanmean(all_bpp) / float(len(all_rms))))
unc_flux_all = (sum(all_rms / all_bpp) *
np.sqrt(np.nanmean(all_bpp) / float(len(all_rms))))
print(">>> error on all pixels in region: {} Jy".format(unc_flux_all))
if full_region_error:
unc_flux = unc_flux_all
avg_rms = np.nanmean(source_rms)
area = len(source_flux) * abs(cd1*cd2)
npix = len(source_flux)
source_peak = np.nanmax(source_flux)
source_bmaj = np.nanmax(source_bmaj)
source_bmin = np.nanmax(source_bmin)
int_bias = 0.
if offset_correct:
hdr = get_header(fitsimage)
if "BIASA" in hdr.keys() and "BIASB" in hdr.keys():
peak_bias = (source_peak/avg_rms)*hdr["BIASA"] + hdr["BIASB"]
logging.info("peak bias: {} Jy/beam".format(peak_bias))
int_bias = (peak_bias / source_peak)*int_flux
logging.info("integrated flux density bias: {} Jy".format(int_bias))
int_flux += int_bias
total_model_flux = 0.
residual_err = 0.
if model_map is not None:
total_model_flux, residual_err = dirtybias_correction(model_flux=model_flux,
residual_flux=residual_flux,
source_bpp=source_bpp,
clean_bias_factor=clean_bias_factor,
clean_bias_std=clean_bias_std)
total_model_flux += int_bias
if blob_correct:
# https://doi.org/10.1111/j.1365-2966.2012.21373.x
eta, err_eta = gaussian_blob_correction(source_peak, avg_rms, sigma)
print(">>> eta = {}".format(eta))
print(">>> flux from {} to {}".format(int_flux, int_flux/eta))
int_flux /= eta
unc_flux = np.sqrt(unc_flux**2 + ((err_eta/eta)*int_flux)**2)
total_model_flux /= eta
# surface brightness
source_sb = int_flux / area
unc_flux = np.sqrt(unc_flux**2 + residual_err**2)
if verbose:
print(">>> The following parameters have been found:\n" \
"............... Int. flux = {0} [Jy]\n" \
"......... Error int. flux = {1} [Jy]\n" \
"............... Peak flux = {2} [Jy/beam]\n" \
".............. No. pixels = {3}\n" \
"...... Surface brightness = {6} [Jy/deg^2]\n"
"............. Source area = {4} [deg^2]\n" \
"............. Average rms = {5} [Jy/beam]\n" \
"........ Total model flux = {7} [Jy]\n".format(\
int_flux, unc_flux, source_peak, npix, area, avg_rms, source_sb, total_model_flux))
return int_flux, unc_flux, source_peak, npix, area, source_bmaj, source_bmin, total_model_flux, avg_rms
def mask(arrays, regions, wcs, fill_value=np.nan):
"""
"""
import pyregion
regions = pyregion.open(regions)
# assume square pixels
cd1 = proj_plane_pixel_scales(wcs)[0]
# cd2 = proj_plane_pixel_scales(wcs)[1]
for region in regions:
x, y = wcs.wcs_world2pix(region.coord_list[0], region.coord_list[1], 0)
r = region.coord_list[2]/cd1
for array in arrays:
print(array.shape)
indices = np.indices(array.shape)
indices_x = indices[0].flatten()
indices_y = indices[1].flatten()
dist = np.sqrt((indices_x-x)**2 + (indices_y-y)**2)
array[indices_y[dist<r], indices_x[dist<r]] = fill_value
return arrays
def measure_brightness_profile(fitsimage, coords, rms, outer_radius, bin_size,
outname,
inner_radius=0.0,
start_angle=0.0,
stop_angle=360.0,
psf=None,
radial_units="arcsec",
brightness_units="mJy",
blank_below=0.,
mask_regions=None):
farray, warray, bpp, cd1, cd2, naxis, beam_major, beam_minor = read_fits(fitsimage)
if rms is not None:
rarray = rms_array(rms, farray)
rarray = np.squeeze(rarray)
if psf is None:
logging.info(">>> using PSF {:.2f}\" times {:.2f}\"".format(beam_major*3600.,
beam_minor*3600.))
bmaj = psf_array(beam_major, farray)
bmin = psf_array(beam_minor, farray)
else:
logging.info(">>> using PSF map from {}".format(psf))
bmaj = psf_array(psf, farray, 0)
bmin = psf_array(psf, farray, 1)
# set pixel scaling so we can strip projection-related effects?
bpp_array = get_bpp(bmaj, bmin, cd1, cd2)
data = farray # Jy/pixel
data[data < blank_below] = 0.
data_rms = rarray
if mask_regions is not None:
data = mask([data], mask_regions, warray, fill_value=0.)[0]
x_c, y_c = warray.all_world2pix(coords[0], coords[1], 0)
print((x_c, y_c))
outer_radius_pix = math.ceil(outer_radius / cd2)
inner_radius_pix = math.floor(inner_radius / cd2)
x, y = np.indices(np.squeeze(data).shape)
x, y = y.flatten(), x.flatten()
r = np.sqrt((x-x_c)**2 + (y-y_c)**2)
print(y.shape, x.shape)
# north-west-south-east; clockwise on the sky
t = np.degrees(np.arctan2(y-y_c, x-x_c))
theta = np.mod(np.degrees(np.arctan2(y-y_c, x-x_c)), 360)
# move from -pi/2 <= theta < pi/2 to 0 < theta < 360:
# theta[np.where(theta <= 0.)] = 180. - theta[np.where(theta <= 0.)]
# theta = np.mod(theta - 180., 360.)
cond1 = r >= inner_radius_pix
cond2 = r <= outer_radius_pix
cond3 = theta >= start_angle
cond4 = theta <= stop_angle
if stop_angle < start_angle:
indices = np.where(cond1 & (cond2 | cond3))
not_indices = np.where(~cond1 | ~cond2 | (~cond3 & ~cond4))
else:
indices = np.where(cond1 & cond2 & cond3 & cond4)
not_indices = np.where(~cond1 | ~cond2 | ~cond3 | ~cond4)
y_i, x_i = y[indices], x[indices]
y_n, x_n = y[not_indices], x[not_indices]
data[y_n, x_n] = 0.
data_rms[y_n, x_n] = 0.
import matplotlib.pyplot as plt
plt.close("all")
plt.imshow(data, vmin=0.00001, vmax=1e-3, origin="lower")
plt.show()
tbin = np.bincount(r.astype("i"), data.flatten())
tbin_rms = np.bincount(r.astype("i"), data_rms.flatten())
tbin_bpp = np.bincount(r.astype("i"), bpp_array.flatten())
nr = np.bincount(r.astype("i"))
radial_profile = tbin / nr
# radial_profile = tbin
radial_profile_rms = tbin_rms / nr
# radial_profile_rms = tbin_rms
bin_size = int(bin_size/(cd2*3600.))
radial_profile_binned = []
radial_profile_rms_binned = []
radius = []
for i in range(0, len(radial_profile)-bin_size, bin_size):
radius.append(np.mean([i, i+bin_size])*cd2)
radial_profile_binned.append(np.nansum(radial_profile[i:i+bin_size]))
radial_profile_rms_binned.append(np.nanmean(radial_profile_rms[i:i+bin_size]))
radius = np.asarray(radius)
radial_profile_binned = np.asarray(radial_profile_binned)
radial_profile_rms_binned = np.asarray(radial_profile_rms_binned)
sector_radii = radius[int(inner_radius_pix)//bin_size:int(outer_radius_pix)//bin_size]
sector_profile = radial_profile_binned[int(inner_radius_pix)//bin_size:int(outer_radius_pix)//bin_size]
sector_rms = radial_profile_rms_binned[int(inner_radius_pix)//bin_size:int(outer_radius_pix)//bin_size]
with open(outname, "w+") as f:
f.write("#brightness,radius\n")
for i in range(len(sector_radii)):
f.write("{},{},{}\n".format(sector_radii[i], sector_profile[i], sector_rms[i]))
def measure_sb_profile(fitsimage, coords, rms, outer_radius, bin_size, outname,
inner_radius=0.,
start_angle=0.,
stop_angle=360.,
psf=None,
blank_below=0.,
mask_regions=None,
flux_scale_err=0.0):
farray, warray, bpp, cd1, cd2, naxis, beam_major, beam_minor = read_fits(fitsimage)
if rms is not None:
rarray = rms_array(rms, farray)
rarray = np.squeeze(rarray)
if psf is None:
logging.info(">>> using PSF {:.2f}\" times {:.2f}\"".format(beam_major*3600.,
beam_minor*3600.))
bmaj = psf_array(beam_major, farray)
bmin = psf_array(beam_minor, farray)
else:
logging.info(">>> using PSF map from {}".format(psf))
bmaj = psf_array(psf, farray, 0)
bmin = psf_array(psf, farray, 1)
# set pixel scaling so we can strip projection-related effects?
bpp_array = get_bpp(bmaj, bmin, cd1, cd2)
data = farray # Jy/pixel
data[data < blank_below] = 0.
data_rms = rarray
if mask_regions is not None:
data = mask([data], mask_regions, warray, fill_value=0.)[0]
x_c, y_c = warray.all_world2pix(coords[0], coords[1], 0)
print((x_c, y_c))
outer_radius_pix = math.ceil(outer_radius / cd2)
inner_radius_pix = math.floor(inner_radius / cd2)
x, y = np.indices(np.squeeze(data).shape)
x, y = y.flatten(), x.flatten()
r = np.sqrt((x-x_c)**2 + (y-y_c)**2)
print(y.shape, x.shape)
# north-west-south-east; clockwise on the sky
t = np.degrees(np.arctan2(y-y_c, x-x_c))
theta = np.mod(np.degrees(np.arctan2(y-y_c, x-x_c)), 360)
# move from -pi/2 <= theta < pi/2 to 0 < theta < 360:
# theta[np.where(theta <= 0.)] = 180. - theta[np.where(theta <= 0.)]
# theta = np.mod(theta - 180., 360.)
cond1 = r >= inner_radius_pix
cond2 = r <= outer_radius_pix
cond3 = theta >= start_angle
cond4 = theta <= stop_angle
if stop_angle < start_angle:
indices = np.where(cond1 & (cond2 | cond3))
not_indices = np.where(~cond1 | ~cond2 | (~cond3 & ~cond4))
else:
indices = np.where(cond1 & cond2 & cond3 & cond4)
not_indices = np.where(~cond1 | ~cond2 | ~cond3 | ~cond4)
y_i, x_i = y[indices], x[indices]
y_n, x_n = y[not_indices], x[not_indices]
r_i = r[indices]
data[y_n, x_n] = np.nan
data_rms[y_n, x_n] = np.nan
import matplotlib.pyplot as plt
plt.close("all")
plt.imshow(data, vmin=0.00001, vmax=1e-3, origin="lower")
plt.show()
radii = []
flux = []
err = []
for i in range(len(y_i)):
radii.append(r_i[i])
flux.append(data[y_i[i], x_i[i]])
err.append(data_rms[y_i[i], x_i[i]])
bindata = np.array([radii, flux, err]).T
bindata_sorted = bindata[bindata[:, 0].argsort()]
bin_size = bin_size/cd2
print(bin_size)
nbins = abs(outer_radius_pix - inner_radius_pix)//bin_size
bin_radii, bin_flux, bin_err = [], [], []
radii = np.asarray(radii)
print(radii)
flux = np.asarray(flux)
err = np.asarray(err)
for i in range(int(nbins)):
bin_radii.append(((i+1)*bin_size - 0.5*bin_size)*cd2)
# tmp_bin_flux = np.nanmean(bindata_sorted[:, 1][np.where(bindata_sorted[:, 0] <= (i+1)*bin_size)])
print((i*bin_size, (i+1)*bin_size))
print(np.where((radii <= (i+1)*bin_size) & (radii > i*bin_size))[0])
bin_flux.append(
np.mean(
flux[np.where((radii <= (i+1)*bin_size) & (radii > i*bin_size))[0]]
)
)
# bin_flux.append(tmp_bin_flux)
# tmp_bin_err = np.nanmean(bindata_sorted[:, 2][np.where(bindata_sorted[:, 0] <= (i+1)*bin_size)])
# bin_err.append(tmp_bin_err)
bin_err.append(
np.nanmean(
err[np.where((radii <= (i+1)*bin_size) & (radii > i*bin_size))[0]]
)
# np.nanstd(flux[np.where((radii <= (i+1)*bin_size) & (radii > i*bin_size))[0]])
)
for i in range(len(bin_err)):
bin_err[i] = np.sqrt(bin_err[i]**2 + (flux_scale_err*bin_flux[i])**2)
with open(outname, "w+") as f:
f.write("#brightness,radius\n")
for i in range(len(bin_radii)):
f.write("{},{},{}\n".format(bin_radii[i], bin_flux[i], bin_err[i]))
def measure_specmap(images, rms, outname):
"""
"""
from scipy.optimize import curve_fit
def powerlaw(x, a, b):
"""Simple powerlaw function."""
return a*(x**b)
def powerlaw_amplitude(y, x, b):
return y/(x**b)
arrays = []
freqs = []
rmses = []
for i in range(len(images)):
farray, _, _, _, _, _, _, _ = read_fits(images[i])
rmses.append(np.squeeze(rms_array(rms[i], farray)))
harray = fits.getheader(images[i])
freqs.append(np.full_like(np.squeeze(farray), find_freq(harray)))
arrays.append(np.squeeze(farray))
if i == 0:
header = harray
arrays = np.stack(arrays)
freqs = np.stack(arrays)
rmses = np.stack(rmses)
print(arrays.shape)
print(freqs.shape)
print(rmses.shape)
alpha = np.full_like(arrays[0, ...], np.nan)
err_alpha = np.full_like(arrays[0, ...], np.nan)
for i in range(len(alpha[:, 0])):
for j in range(len(alpha[:, 1])):
popt, pcov = curve_fit(powerlaw, freqs[:, i, j], arrays[:, i, j],
[powerlaw_amplitude(arrays[0, i, j], freqs[0, i, j], -1), -1.],
absolute_sigma=True,
method="lm",
sigma=rmses[:, i, j],
maxfev=10000)
perr = np.sqrt(np.diag(pcov))
alpha[i, j] = popt[1]
err_alpha[i, j] = perr[1]
fits.writeto(outname, alpha, header, overwrite=True)
fits.writeto(outname.replace(".fits", "_err.fits"), err_alpha, header, overwrite=True)
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