The version of pysynphot used for this investigation was:
URL: https://svn.stsci.edu/svn/ssb/astrolib/tags/pysynphot_v0.61_ETC18.0
Repository Root: https://svn.stsci.edu/svn/ssb/astrolib
Revision: 1143
Last Changed Author: laidler
Last Changed Rev: 1080
Last Changed Date: 2009-08-14 14:57:05 -0400 (Fri, 14 Aug 2009)
#Examine spectrum as presented in CDBS:
sp=S.FileSpectrum('/grp/hst/cdbs/calspec/lds749b_mod_001.fits')
clf()
plot(sp.wave,sp.flux)
xlabel(sp.waveunits)
ylabel(sp.fluxunits)
title(sp)
xlim(1100,1500)
savefig('cdbs_flam.png')
#Examine bin widths of spectrum:
dw=sp.wave[1:]-sp.wave[:-1]
plot(sp.wave[1:],dw,'.')
xlabel('angstrom')
ylabel('binwidth')
title(sp)
savefig('binwidth.png')
xlim(1100,1500)
ylim(0,0.6)
savefig('binwidth_zoom.png')
#Previously obtain and save SYNPHOT spectrum using calcspec task:
#--> lpar calcspec
# spectrum = "crcalspec$lds749b_mod_001.fits" Spectrum to calculate
# output = "lds749b.fits" Output table name
# (form = "counts") Desired form of output spectrum
#Read in this spectrum to examine its wavelength array:
synspec=S.FileSpectrum('lds749b.fits')
syndw=synspec.wave[1:]-synspec.wave[:-1]
plot(synspec.wave[1:],syndw,'.')
xlabel('angstrom')
ylabel('binwidth')
title('crcalspec$lds749b_mod_001.fits rendered in SYNPHOT')
savefig('syn_binwidth.png')
xlim(1100,1500)
ylim(0,.6)
savefig('syn_binwidth_zoom.png')
#Examine the spectrum in pysynphot on the SYNPHOT waveset:
sp.convert('counts')
plot(synspec.wave,sp.sample(synspec.wave),'.-')
xlim(1100,1500)
ylim(0,30)
xlabel(synspec.waveunits)
ylabel(sp.fluxunits)
title("%s sampled on SYNPHOT wavelength array"%os.path.basename(str(sp)))
savefig('syn_sampled_counts.png')