diff options
Diffstat (limited to 'lib/stwcs/wcsutil/headerlet.py')
| -rw-r--r-- | lib/stwcs/wcsutil/headerlet.py | 38 |
1 files changed, 34 insertions, 4 deletions
diff --git a/lib/stwcs/wcsutil/headerlet.py b/lib/stwcs/wcsutil/headerlet.py index 54fb733..a0e87ca 100644 --- a/lib/stwcs/wcsutil/headerlet.py +++ b/lib/stwcs/wcsutil/headerlet.py @@ -1,3 +1,14 @@ +""" +This module implements headerlets. + +A headerlet serves as a mechanism for encapsulating WCS information +which can be used to update the WCS solution of an image. The idea +came up first from the desire for passing improved astrometric +solutions for HST data and provide those solutions in a manner +that would not require getting entirely new images from the archive +when only the WCS information has been updated. + +""" from __future__ import division import logging import os @@ -1368,7 +1379,8 @@ def headerlet_summary(filename, columns=None, pad=2, maxwidth=None, for key in COLUMN_DICT: summary_dict[kw][key].extend(ext_summary[kw][key]) except: - print 'Skipping headerlet...Could not read Headerlet from extension ',hdrlet_indx + print "Skipping headerlet" + print "Could not read Headerlet from extension ", hdrlet_indx if close_fobj: fobj.close() @@ -1720,7 +1732,7 @@ def archive_as_headerlet(filename, hdrname, sciext='SCI', fobj.flush() else: print 'WARNING:' - print ' Headerlet with hdrname ', hdrname, ' already archived for WCS ',wcsname + print ' Headerlet with hdrname ', hdrname, ' already archived for WCS ', wcsname print ' No new headerlet appended to ', fname, '.' if close_fobj: @@ -1921,7 +1933,7 @@ class Headerlet(pyfits.HDUList): siphdr = self[('SIPWCS', idx)].header.ascard if dist_models_equal: - hwcs = HSTWCS(fobj,ext=('SCI', idx)) + hwcs = HSTWCS(fobj, ext=('SCI', idx)) hwcshdr = hwcs.wcs2header(sip2hdr=not(dist_models_equal)) # a minimal attempt to get the position of the WCS keywords group @@ -2233,13 +2245,17 @@ class Headerlet(pyfits.HDUList): return summary_cols, summary def hverify(self): + """ + Verify the headerlet file is a valid fits file and has + the required Primary Header keywords + """ self.verify() header = self[0].header assert('DESTIM' in header and header['DESTIM'].strip()) assert('HDRNAME' in header and header['HDRNAME'].strip()) assert('UPWCSVER' in header) - def verify_hdrname(self,dest): + def verify_hdrname(self, dest): """ Verifies that the headerlet can be applied to the observation @@ -2274,6 +2290,20 @@ class Headerlet(pyfits.HDUList): return False def tofile(self, fname, destim=None, hdrname=None, clobber=False): + """ + Write this headerlet to a file + + Parameters + ---------- + fname: string + file name + destim: string (optional) + provide a value for DESTIM keyword + hdrname: string (optional) + provide a value for HDRNAME keyword + clobber: boolean + a flag which allows to overwrte an existing file + """ if not destim or not hdrname: self.hverify() self.writeto(fname, clobber=clobber) |