diff options
Diffstat (limited to 'astro')
| -rwxr-xr-x | astro/fitting/fit_beta_model.py | 133 | ||||
| -rwxr-xr-x | astro/fitting/fit_betasbp_cut.py | 237 |
2 files changed, 237 insertions, 133 deletions
diff --git a/astro/fitting/fit_beta_model.py b/astro/fitting/fit_beta_model.py deleted file mode 100755 index aaf5781..0000000 --- a/astro/fitting/fit_beta_model.py +++ /dev/null @@ -1,133 +0,0 @@ -#!/usr/bin/env python3 -# -*- coding: utf-8 -*- -# -# Fitting data according to (SBP) beta model. -# -# Aaron LI -# 2015/05/29 - - -import numpy as np -from scipy.optimize import curve_fit - -import os -import sys -import getopt -import re - - -USAGE = """Usage: - %(prog)s [ -h -c -o outfile ] -i infile - -Required arguments: - -i, --infile - input data file with the following *four* columns: - r, rerr, s, serr - -o, --outfile - output file to store the fitted data - if not provided, then print results to screen - -Optional arguments: - -h, --help - print this usage - -c, --cut - accept an integer number - ignore the inner-most n data points -""" % { 'prog': os.path.basename(sys.argv[0]) } - - -def usage(): - print(USAGE) - - -def beta_model(r, s0, rc, beta, c): - """ - SBP beta model. - """ - return s0 * np.power((1.0+(r/rc)**2), 0.5-3*beta) + c - - -def main(): - infile = None - outfilename= None - cut = 0 - - try: - opts, args = getopt.getopt(sys.argv[1:], 'c:hi:o:', - ['cut=', 'help', 'infile=', 'outfile=']) - except getopt.GetoptError as e: - print(e, file=sys.stderr) - usage() - sys.exit(2) - - for opt, arg in opts: - if opt in ('-h', '--help'): - usage() - sys.exit(0) - elif opt in ('-i', '--infile'): - infile = arg - elif opt in ('-o', '--outfile'): - outfilename = arg - elif opt in ('-c', '--cut'): - cut = int(arg) - else: - assert False, 'unhandled option' - - if not infile: - print('ERROR: --infile required', file=sys.stderr) - sys.exit(11) - if outfilename: - outfile = open(outfilename, 'w') - else: - outfile = sys.stdout - - # input data list - r_data = [] - rerr_data = [] - s_data = [] - serr_data = [] - - for line in open(infile, 'r'): - if re.match(r'^\s*#', line): - continue - if re.match(r'^\s*$', line): - continue - r, rerr, s, serr = map(float, line.split()) - r_data.append(r) - rerr_data.append(rerr) - s_data.append(s) - serr_data.append(serr) - - # convert to numpy array - r_data = np.array(r_data) - rerr_data = np.array(rerr_data) - s_data = np.array(s_data) - serr_data = np.array(serr_data) - - # initial parameter values for beta model - s0_0 = 1.0e-7 - rc_0 = 10.0 - beta_0 = 0.6 - c_0 = 0.0 - par_0 = [s0_0, rc_0, beta_0, c_0] - - par_fit, cov_fit = curve_fit(beta_model, r_data[cut:], s_data[cut:], - p0=par_0, sigma=serr_data[cut:]) - - s_fitted = beta_model(r_data, *par_fit) - - print("# beta-model fitting results:", file=outfile) - print("# s0 * power((1.0+(r/rc)**2), 0.5-3*beta) + c", file=outfile) - print("# s0 = %g, rc = %g, beta = %g, c = %g" % tuple(par_fit), - file=outfile) - print("# radius(input) brightness(fitted)", file=outfile) - for i in range(len(s_fitted)): - print("%g %g" % (r_data[i], s_fitted[i]), file=outfile) - - if not outfilename: - outfile.close() - - -if __name__ == '__main__': - main() - diff --git a/astro/fitting/fit_betasbp_cut.py b/astro/fitting/fit_betasbp_cut.py new file mode 100755 index 0000000..4b530f4 --- /dev/null +++ b/astro/fitting/fit_betasbp_cut.py @@ -0,0 +1,237 @@ +#!/usr/bin/env python3 +# -*- coding: utf-8 -*- +# +# To fitting the given SBP data with the following beta model: +# s = s0 * pow((1.0+(r/rc)^2), 0.5-3*beta) + c +# And this tool supports the following two requirements for the fitting: +# (1) ignore the specified number of inner-most data points; +# (2) ignore the data points whose radius value less than the given value. +# +# Aaron LI +# 2015/05/29 +# +# Changelogs: +# 2015/05/30: +# * Added option '-n' / '--no-radius' to ignore radius less than the +# given value. +# * Support read model initial parameter values from input file. +# + + +from __future__ import print_function, division + +import numpy as np +from scipy.optimize import curve_fit + +import os +import sys +import getopt +import re + + +# modes of to cut data +CUT_POINT = 'CUT_POINT' +CUT_RADIUS = 'CUT_RADIUS' + + +def beta_model(r, s0, rc, beta, c): + """ + SBP beta model, with a constant background. + """ + return s0 * np.power((1.0+(r/rc)**2), 0.5-3*beta) + c + + +def fit_beta_model(xdata, ydata, yerrdata, p0, + cutmode=CUT_POINT, cutvalue=0): + """ + Fit the provided data with the beta model. + + Arguments: + p0: initial values for the parameters of beta model + cutmode: 'point' / 'radius'; ignore data by number of data points, + or by radius value less than the given value + cutvalue: the cut limit + + Return: + [fitted_par, fitted_cov, fitted_model_value] + """ + if cutmode == CUT_POINT: + xdata2 = xdata[cutvalue:] + ydata2 = ydata[cutvalue:] + yerrdata2 = yerrdata[cutvalue:] + elif cutmode == CUT_RADIUS: + ii = xdata >= cutvalue + xdata2 = xdata[ii] + ydata2 = ydata[ii] + yerrdata2 = yerrdata[ii] + else: + raise ValueError('Unknown cut mode: %s' % cutmode) + par_fit, cov_fit = curve_fit(beta_model, xdata2, ydata2, + p0=p0, sigma=yerrdata2) + y_fit = beta_model(xdata, *par_fit) + return (par_fit, cov_fit, y_fit) + + +def main(): + # options + infile = None + outfilename= None + cutmode = CUT_POINT # ignore data by number of data points + cutvalue = 0 # do not ignore any data by default + # initial values for the four parameters of the beta model + s0_0 = 1.0e-7 + rc_0 = 10.0 + beta_0 = 0.6 + c_0 = 0.0 + # debug + verbose = False + + try: + opts, args = getopt.getopt(sys.argv[1:], 'c:hi:n:o:v', + ['cut-point=', 'help', 'infile=', 'no-radius=', + 'outfile=', 'verbose']) + except getopt.GetoptError as e: + print(e, file=sys.stderr) + usage() + sys.exit(2) + + for opt, arg in opts: + if opt in ('-h', '--help'): + usage() + sys.exit(0) + elif opt in ('-v', '--verbose'): + verbose = True + elif opt in ('-i', '--infile'): + infile = arg + elif opt in ('-o', '--outfile'): + outfilename = arg + elif opt in ('-c', '--cut-point'): + cutvalue = int(arg) + cutmode = CUT_POINT + elif opt in ('-n', '--no-radius'): + cutvalue = float(arg) + cutmode = CUT_RADIUS + else: + assert False, 'unhandled option' + + if not infile: + print('ERROR: --infile required', file=sys.stderr) + sys.exit(11) + if outfilename: + outfile = open(outfilename, 'w') + else: + outfile = sys.stdout + + # input data list + r_data = [] + rerr_data = [] + s_data = [] + serr_data = [] + + # regex to match initial parameter names, blank line, and comment line + re_blank = re.compile(r'^\s*$') + re_comment = re.compile(r'^\s*#') + re_s0 = re.compile(r'^\s*#\s*s0_0\s*[:=]') + re_rc = re.compile(r'^\s*#\s*rc_0\s*[:=]') + re_beta = re.compile(r'^\s*#\s*beta_0\s*[:=]') + re_c = re.compile(r'^\s*#\s*c_0\s*[:=]') + for line in open(infile, 'r'): + if re_s0.match(line): + # read 's0_0': initial value for parameter 's0' + s0_0 = float(re_s0.split(line)[1]) + elif re_rc.match(line): + # read 'rc_0': initial value for parameter 'rc' + rc_0 = float(re_rc.split(line)[1]) + elif re_beta.match(line): + # read 'beta_0': initial value for parameter 'beta' + beta_0 = float(re_beta.split(line)[1]) + elif re_c.match(line): + # read 'c_0': initial value for parameter 'c' + c_0 = float(re_c.split(line)[1]) + elif re_blank.match(line): + # ignore blank line + continue + elif re_comment.match(line): + # ignore comment line + continue + else: + try: + r, rerr, s, serr = map(float, line.split()) + except ValueError: + try: + r, s, serr = map(float, line.split()) + rerr = 0.0 + except ValueError: + print('ERROR: unsupported input data format', + file=sys.stderr) + sys.exit(21) + r_data.append(r) + rerr_data.append(rerr) + s_data.append(s) + serr_data.append(serr) + + # convert to numpy array + r_data = np.array(r_data) + rerr_data = np.array(rerr_data) + s_data = np.array(s_data) + serr_data = np.array(serr_data) + + if verbose: + print('DEBUG: s0_0 = %g, rc_0 = %g, beta_0 = %g, c_0 = %g' % \ + (s0_0, rc_0, beta_0, c_0), file=sys.stderr) + + par_0 = [s0_0, rc_0, beta_0, c_0] + + par_fit, cov_fit, s_fit = fit_beta_model(r_data, s_data, serr_data, + p0=par_0, cutmode=cutmode, cutvalue=cutvalue) + + print("# beta-model fitting results:", file=outfile) + print("# s(r) = s0 * pow((1.0+(r/rc)^2), 0.5-3*beta) + c", file=outfile) + print("# s0 = %g\n# rc = %g\n# beta = %g\n# c = %g" % tuple(par_fit), + file=outfile) + print("# radius(input) brightness(fitted)", file=outfile) + for i in range(len(s_fit)): + print("%g %g" % (r_data[i], s_fit[i]), file=outfile) + + if outfilename: + outfile.close() + + +USAGE = """Usage: + %(prog)s [ -h -c -o outfile ] -i infile + +Required arguments: + -i, --infile + input data file with the following *four* or *three* columns: + r, rerr, s, serr + r, s, serr + Note: the initial values for beta model paramters can also be + provided with the following syntax: + # s0_0 = ?? + # rc_0 = ?? + # beta_0 = ?? + # c_0 = ?? + -o, --outfile + output file to store the fitted data + if not provided, then print results to screen + +Optional arguments: + -h, --help + print this usage + -c, --cut-point + accept an integer number (n) + ignore the inner-most n data points + -n, --no-radius + accept a float number (r) + ignore the data points whose radius is less than r +""" % { 'prog': os.path.basename(sys.argv[0]) } + + +def usage(): + print(USAGE) + + +if __name__ == '__main__': + main() + + |