Should fix most problems in stwcs due to pyfits Header updates. The main issue that caused incompatibility is that slices of headers (including by wildcard patterns) now returns a new Header rather than a list of cards.

git-svn-id: http://svn.stsci.edu/svn/ssb/stsci_python/stsci_python/trunk/stwcs@15198 fe389314-cf27-0410-b35b-8c050e845b92

6 files changed, 263 insertions, 263 deletions

diff --git a/lib/stwcs/wcsutil/altwcs.py b/lib/stwcs/wcsutil/altwcs.py
index 064b2ca..d68a0d8 100644
--- a/lib/stwcs/wcsutil/altwcs.py
+++ b/lib/stwcs/wcsutil/altwcs.py
@@ -35,9 +35,9 @@ def archiveWCS(fname, ext, wcskey=" ", wcsname=" ", reusekey=False):
 
     Examples
     --------
-    Copy the primary WCS of an in memory headrlet object to an 
+    Copy the primary WCS of an in memory headrlet object to an
     alternate WCS with key 'T'
-    
+
     >>> hlet=headerlet.createHeaderlet('junk.fits', 'hdr1.fits')
     >>> altwcs.wcskeys(hlet[1].header)
     ['A']
@@ -45,7 +45,7 @@ def archiveWCS(fname, ext, wcskey=" ", wcsname=" ", reusekey=False):
     >>> altwcs.wcskeys(hlet[1].header)
     ['A', 'T']
 
-    
+
     See Also
     --------
     wcsutil.restoreWCS: Copy an alternate WCS to the primary WCS
@@ -63,10 +63,10 @@ def archiveWCS(fname, ext, wcskey=" ", wcsname=" ", reusekey=False):
 
     # Interpret input 'ext' value to get list of extensions to process
     ext = _buildExtlist(f, ext)
-        
+
     if not wcskey and not wcsname:
         raise KeyError("Either wcskey or wcsname should be specified")
-    
+
     wcsext = ext[0]
     if wcskey != " " and wcskey in wcskeys(f[wcsext].header) and not reusekey:
         closefobj(fname, f)
@@ -112,23 +112,23 @@ def archiveWCS(fname, ext, wcskey=" ", wcsname=" ", reusekey=False):
     else:
         wkey = wcskey
         wname = wcsname
-    
+
     for e in ext:
         hwcs = readAltWCS(f,e,wcskey=' ')
         if hwcs is None:
             continue
 
         wcsnamekey = 'WCSNAME' + wkey
-        f[e].header.update(key=wcsnamekey, value=wname)
+        f[e].header[wcsnamekey] = wname
 
         try:
             old_wcsname=hwcs.pop('WCSNAME')
         except:
             pass
         for k in hwcs.keys():
-            
+
             key = k[:7] + wkey
-            f[e].header.update(key=key, value=hwcs[k])
+            f[e].header[key] = hwcs[k]
     closefobj(fname, f)
 
 def restore_from_to(f, fromext=None, toext=None, wcskey=" ", wcsname=" "):
@@ -138,16 +138,16 @@ def restore_from_to(f, fromext=None, toext=None, wcskey=" ", wcsname=" "):
     Reads in a WCS defined with wcskey and saves it as the primary WCS.
     Goes sequentially through the list of extensions in ext.
     Alternatively uses 'fromext' and 'toext'.
-    
+
 
     Parameters
     ----------
     f:       string or pyfits.HDUList object
              a file name or a file object
-    fromext: string 
+    fromext: string
              extname from which to read in the alternate WCS, for example 'SCI'
     toext:   string or python list
-             extname or a list of extnames to which the WCS will be copied as 
+             extname or a list of extnames to which the WCS will be copied as
              primary, for example ['SCI', 'ERR', 'DQ']
     wcskey:  a charater
              "A"-"Z" - Used for one of 26 alternate WCS definitions.
@@ -177,16 +177,16 @@ def restore_from_to(f, fromext=None, toext=None, wcskey=" ", wcsname=" "):
         toext = [toext]
 
     # the case of an HDUList object in memory without an associated file
-    
-    #if fobj.filename() is not None: 
+
+    #if fobj.filename() is not None:
     #        name = fobj.filename()
-            
+
     simplefits = fu.isFits(fobj)[1] is 'simple'
     if simplefits:
         wcskeyext = 0
     else:
         wcskeyext = 1
-        
+
     if wcskey == " ":
         if wcsname.strip():
             wkey = getKeyFromName(fobj[wcskeyext].header, wcsname)
@@ -199,7 +199,7 @@ def restore_from_to(f, fromext=None, toext=None, wcskey=" ", wcsname=" "):
             closefobj(f, fobj)
             return
         wkey = wcskey
-    
+
     countext = fu.countExtn(fobj, fromext)
     if not countext:
         raise KeyError("File does not have extension with extname %s", fromext)
@@ -211,7 +211,7 @@ def restore_from_to(f, fromext=None, toext=None, wcskey=" ", wcsname=" "):
     if fobj.filename() is not None:
         #fobj.writeto(name)
         closefobj(f, fobj)
-        
+
 def restoreWCS(f, ext, wcskey=" ", wcsname=" "):
     """
     Copy a WCS with key "WCSKEY" to the primary WCS
@@ -219,7 +219,7 @@ def restoreWCS(f, ext, wcskey=" ", wcsname=" "):
     Reads in a WCS defined with wcskey and saves it as the primary WCS.
     Goes sequentially through the list of extensions in ext.
     Alternatively uses 'fromext' and 'toext'.
-    
+
 
     Parameters
     ----------
@@ -255,16 +255,16 @@ def restoreWCS(f, ext, wcskey=" ", wcsname=" "):
 
 
     # the case of an HDUList object in memory without an associated file
-    
-    #if fobj.filename() is not None: 
+
+    #if fobj.filename() is not None:
     #        name = fobj.filename()
-            
+
     simplefits = fu.isFits(fobj)[1] is 'simple'
     if simplefits:
         wcskeyext = 0
     else:
         wcskeyext = 1
-        
+
     if wcskey == " ":
         if wcsname.strip():
             wkey = getKeyFromName(fobj[wcskeyext].header, wcsname)
@@ -277,11 +277,11 @@ def restoreWCS(f, ext, wcskey=" ", wcsname=" "):
             closefobj(f, fobj)
             return
         wkey = wcskey
-        
-    
+
+
     for e in ext:
         _restore(fobj, wkey, fromextnum=e)
-    
+
     if fobj.filename() is not None:
         #fobj.writeto(name)
         closefobj(f, fobj)
@@ -325,10 +325,10 @@ def deleteWCS(fname, ext, wcskey=" ", wcsname=" "):
         wcskeyext = 0
     else:
         wcskeyext = 1
-        
+
     if not wcskeys and not wcsname:
         raise KeyError("Either wcskey or wcsname should be specified")
-    
+
     if wcskey == " ":
         # try getting the key from WCSNAME
         wkey = getKeyFromName(fobj[wcskeyext].header, wcsname)
@@ -336,11 +336,11 @@ def deleteWCS(fname, ext, wcskey=" ", wcsname=" "):
             closefobj(fname, fobj)
             raise KeyError("Could not get a key: wcsname '%s' not found in header." % wcsname)
     else:
-        if wcskey not in wcskeys(fobj[wcskeyext].header):            
+        if wcskey not in wcskeys(fobj[wcskeyext].header):
             closefobj(fname, fobj)
             raise KeyError("Could not find alternate WCS with key %s in this file" % wcskey)
         wkey = wcskey
-        
+
     prexts = []
     for i in ext:
         hdr = fobj[i].header
@@ -359,10 +359,10 @@ def deleteWCS(fname, ext, wcskey=" ", wcsname=" "):
 
 def _buildExtlist(fobj, ext):
     """
-    Utility function to interpret the provided value of 'ext' and return a list 
-    of 'valid' values which can then be used by the rest of the functions in 
+    Utility function to interpret the provided value of 'ext' and return a list
+    of 'valid' values which can then be used by the rest of the functions in
     this module.
-    
+
     Parameters
     ----------
     fobj: HDUList
@@ -373,7 +373,7 @@ def _buildExtlist(fobj, ext):
             with WCSs to be archived
     """
     if not isinstance(ext,list):
-        if isinstance(ext,str):    
+        if isinstance(ext,str):
             extstr = ext
             ext = []
             for extn in range(1, len(fobj)):
@@ -434,7 +434,7 @@ def _check_headerpars(fobj, ext):
     if not isinstance(fobj, pyfits.Header) and not isinstance(fobj, pyfits.HDUList) \
                    and not isinstance(fobj, str):
         raise ValueError("Expected a file name, a file object or a header\n")
-    
+
     if not isinstance(fobj, pyfits.Header):
         #raise ValueError("Expected a valid ext parameter when input is a file")
         if not isinstance(ext, int) and not isinstance(ext, tuple):
@@ -448,7 +448,7 @@ def _getheader(fobj, ext):
     else:
         hdr = fobj[ext].header
     return hdr
-        
+
 def readAltWCS(fobj, ext, wcskey=' ',verbose=False):
     """ Reads in alternate WCS from specified extension
 
@@ -461,12 +461,12 @@ def readAltWCS(fobj, ext, wcskey=' ',verbose=False):
         alternate/primary WCS key that will be replaced by the new key
     ext: int
         extension number
-    
+
     Returns
     -------
     hdr: pyfits.Header
         header object with ONLY the keywords for specified alternate WCS
-    """    
+    """
     if isinstance(fobj, str):
         fobj = pyfits.open(fobj)
 
@@ -475,33 +475,33 @@ def readAltWCS(fobj, ext, wcskey=' ',verbose=False):
         nwcs = pywcs.WCS(hdr, fobj=fobj, key=wcskey)
     except KeyError:
         if verbose:
-            print 'readAltWCS: Could not read WCS with key %s' %wcskey 
+            print 'readAltWCS: Could not read WCS with key %s' %wcskey
             print '            Skipping %s[%s]' % (fobj.filename(), str(ext))
         return None
     hwcs = nwcs.to_header()
 
     if nwcs.wcs.has_cd():
         hwcs = pc2cd(hwcs, key=wcskey)
-    
+
     return hwcs
-    
+
 def convertAltWCS(fobj,ext,oldkey=" ",newkey=' '):
-    """ 
-    Translates the alternate/primary WCS with one key to an alternate/primary WCS with 
+    """
+    Translates the alternate/primary WCS with one key to an alternate/primary WCS with
     another key.
-    
+
     Parameters
     ----------
     fobj: string, pyfits.HDUList, or pyfits.Header
-        fits filename, pyfits file object or pyfits header 
+        fits filename, pyfits file object or pyfits header
         containing alternate/primary WCS(s) to be converted
     ext: int
         extension number
     oldkey: string [" ",A-Z]
         alternate/primary WCS key that will be replaced by the new key
     newkey: string [" ",A-Z]
-        new alternate/primary WCS key 
-    
+        new alternate/primary WCS key
+
     Returns
     -------
     hdr: pyfits.Header
@@ -530,14 +530,14 @@ def wcskeys(fobj, ext=None):
     fobj: string, pyfits.HDUList or pyfits.Header
           fits file name, pyfits file object or pyfits header
     ext: int or None
-         extension number 
+         extension number
          if None, fobj must be a header
     """
     _check_headerpars(fobj, ext)
     hdr = _getheader(fobj, ext)
     names = hdr["WCSNAME*"]
     d = []
-    for key in names.keys():
+    for key in names:
         wkey = key.replace('WCSNAME','')
         if wkey == '': wkey = ' '
         d.append(wkey)
@@ -552,18 +552,18 @@ def wcsnames(fobj, ext=None):
     fobj: string, pyfits.HDUList or pyfits.Header
           fits file name, pyfits file object or pyfits header
     ext: int or None
-         extension number 
+         extension number
          if None, fobj must be a header
-    
+
     """
     _check_headerpars(fobj, ext)
     hdr = _getheader(fobj, ext)
     names = hdr["WCSNAME*"]
     d = {}
-    for c in names:
-        wkey = c.key.replace('WCSNAME','')
+    for keyword, value in names.items():
+        wkey = keyword.replace('WCSNAME','')
         if wkey == '': wkey = ' '
-        d[wkey] = c.value
+        d[wkey] = value
     return d
 
 def available_wcskeys(fobj, ext=None):
@@ -577,7 +577,7 @@ def available_wcskeys(fobj, ext=None):
     fobj: string, pyfits.HDUList or pyfits.Header
           fits file name, pyfits file object or pyfits header
     ext: int or None
-         extension number 
+         extension number
          if None, fobj must be a header
     """
     _check_headerpars(fobj, ext)
@@ -600,7 +600,7 @@ def next_wcskey(fobj, ext=None):
     fobj: string, pyfits.HDUList or pyfits.Header
           fits file name, pyfits file object or pyfits header
     ext: int or None
-         extension number 
+         extension number
          if None, fobj must be a header
     """
     _check_headerpars(fobj, ext)
@@ -661,7 +661,7 @@ def pc2cd(hdr, key=' '):
 def _parpasscheck(fobj, ext, wcskey, fromext=None, toext=None, reusekey=False):
     """
     Check input parameters to altwcs functions
-    
+
     fobj:    string or pyfits.HDUList object
              a file name or a file object
     ext:     an int, a tuple, a python list of integers or a python list
@@ -677,10 +677,10 @@ def _parpasscheck(fobj, ext, wcskey, fromext=None, toext=None, reusekey=False):
     if not isinstance(fobj,pyfits.HDUList):
         print "First parameter must be a fits file object or a file name."
         return False
-    
-    # first one covers the case of an object created in memory 
+
+    # first one covers the case of an object created in memory
     # (e.g. headerlet) for which fileinfo returns None
-    if fobj.fileinfo(0) is None: 
+    if fobj.fileinfo(0) is None:
         pass
     else:
         # an HDUList object with associated file
@@ -694,7 +694,7 @@ def _parpasscheck(fobj, ext, wcskey, fromext=None, toext=None, reusekey=False):
         print "Ext must be integer, tuple, string,a list of int extension numbers, \n\
         or a list of tuples representing a fits extension, for example ('sci', 1)."
         return False
-    
+
     if not isinstance(fromext, str) and fromext is not None:
         print "fromext must be a string representing a valid extname"
         return False
@@ -703,11 +703,11 @@ def _parpasscheck(fobj, ext, wcskey, fromext=None, toext=None, reusekey=False):
                      toext is not None :
         print "toext must be a string or a list of strings representing extname"
         return False
-    
+
     if len(wcskey) != 1:
         print 'Parameter wcskey must be a character - one of "A"-"Z" or " "'
         return False
-    
+
     return True
 
 def closefobj(fname, f):
diff --git a/lib/stwcs/wcsutil/convertwcs.py b/lib/stwcs/wcsutil/convertwcs.py
index 80276c3..0fa61af 100644
--- a/lib/stwcs/wcsutil/convertwcs.py
+++ b/lib/stwcs/wcsutil/convertwcs.py
@@ -65,7 +65,7 @@ def archive_prefix_OPUS_WCS(fobj,extname='SCI'):
         for key in wcskeys:
             okey = 'O'+key[:7]
             hdr = fobj[(extname,e)].header
-            if hdr.has_key(okey):
+            if okey in hdr:
                 # Update alternate WCS keyword with prefix-O OPUS keyword value
                 hdr[key] = hdr[okey]
 
@@ -102,7 +102,7 @@ def create_prefix_OPUS_WCS(fobj,extname='SCI'):
             raise IOError
 
     # check for existance of O-prefix WCS
-    if not fobj['sci',1].header.has_key(owcskeys[0]):
+    if owcskeys[0] not in fobj['sci',1].header:
 
         # find out how many SCI extensions are in the image
         numextn = fileutil.countExtn(fobj,extname=extname)
@@ -111,7 +111,7 @@ def create_prefix_OPUS_WCS(fobj,extname='SCI'):
         for extn in xrange(1,numextn+1):
             hdr = fobj[(extname,extn)].header
             for okey in owcskeys:
-                hdr.update(okey,hdr[okey[1:]+'O'])
+                hdr[okey] = hdr[okey[1:]+'O']
 
     # Close FITS image if we had to open it...
     if closefits:
diff --git a/lib/stwcs/wcsutil/getinput.py b/lib/stwcs/wcsutil/getinput.py
index 2f64f46..bfe4234 100644
--- a/lib/stwcs/wcsutil/getinput.py
+++ b/lib/stwcs/wcsutil/getinput.py
@@ -21,12 +21,11 @@ def parseSingleInput(f=None, ext=None):
             else:
                 extnum = ext
         phdu = pyfits.open(filename)
-        hdr0 = pyfits.getheader(filename)
+        hdr0 = phdu[0].header
         try:
-            ehdr = pyfits.getheader(filename, ext=extnum)
-        except (IndexError,KeyError):
-            print 'Unable to get extension.', extnum
-            raise
+            ehdr = phdu[extnum].header
+        except (IndexError, KeyError), e:
+            raise e.__class__('Unable to get extension %s.' % extnum)
 
     elif isinstance(f, pyfits.HDUList):
         phdu = f
@@ -37,9 +36,10 @@ def parseSingleInput(f=None, ext=None):
         ehdr = f[extnum].header
         hdr0 = f[0].header
         filename = hdr0.get('FILENAME', "")
-        
+
     else:
-        raise ValueError('Input must be a file name string or a pyfits file object')
+        raise ValueError('Input must be a file name string or a pyfits file '
+                         'object')
 
     return filename, hdr0, ehdr, phdu
 
@@ -59,4 +59,4 @@ def parseMultipleInput(input):
             return input
         else:
             filelist = input[:]
-    return filelist
\ No newline at end of file
+    return filelist
diff --git a/lib/stwcs/wcsutil/headerlet.py b/lib/stwcs/wcsutil/headerlet.py
index 37738f9..da7b6dc 100644
--- a/lib/stwcs/wcsutil/headerlet.py
+++ b/lib/stwcs/wcsutil/headerlet.py
@@ -451,21 +451,17 @@ def update_ref_files(source, dest):
     """
     logger.info("Updating reference files")
     phdukw = {'IDCTAB': True,
-            'NPOLFILE': True,
-            'D2IMFILE': True}
+              'NPOLFILE': True,
+              'D2IMFILE': True}
 
-    if 'HISTORY' in dest:
-        wind = dest.ascard.index_of('HISTORY')
-    else:
-        wind = len(dest)
-
-    for key in phdukw.keys():
+    for key in phdukw:
         try:
-            srckey = source.ascard[key]
-            dest.update(key, srckey.value, after=wind, comment=srckey.comment)
+            try:
+                del dest[key]
+            except:
+                pass
+            dest.append((key, source[key], source.comments[key]), bottom=True)
         except KeyError:
-            # TODO: I don't understand what the point of this is.  Is it meant
-            # for logging purposes?  Right now it isn't used.
             phdukw[key] = False
     return phdukw
 
@@ -474,10 +470,11 @@ def get_rootname(fname):
     returns the value of ROOTNAME or DESTIM
     """
 
+    hdr = pyfits.getheader(fname)
     try:
-        rootname = pyfits.getval(fname, 'ROOTNAME')
+        rootname = hdr['ROOTNAME']
     except KeyError:
-        rootname = pyfits.getval(fname, 'DESTIM')
+        rootname = hdr['DESTIM']
     return rootname
 
 def print_summary(summary_cols, summary_dict, pad=2, maxwidth=None, idcol=None,
@@ -554,25 +551,32 @@ def _create_primary_HDU(destim, hdrname, distname, wcsname,
 
     # build Primary HDU
     phdu = pyfits.PrimaryHDU()
-    phdu.header.update('DESTIM', destim,
-                       comment='Destination observation root name')
-    phdu.header.update('HDRNAME', hdrname, comment='Headerlet name')
+    phdu.header['DESTIM'] = (destim, 'Destination observation root name')
+    phdu.header['HDRNAME'] = (hdrname, 'Headerlet name')
     fmt = "%Y-%m-%dT%H:%M:%S"
-    phdu.header.update('DATE', time.strftime(fmt),
-                       comment='Date FITS file was generated')
-    phdu.header.update('WCSNAME', wcsname, comment='WCS name')
-    phdu.header.update('DISTNAME', distname, comment='Distortion model name')
-    phdu.header.update('SIPNAME', sipname, comment='origin of SIP polynomial distortion model')
-    phdu.header.update('NPOLFILE', npolfile, comment='origin of non-polynmial distortion model')
-    phdu.header.update('D2IMFILE', d2imfile, comment='origin of detector to image correction')
-    phdu.header.update('AUTHOR', author, comment='headerlet created by this user')
-    phdu.header.update('DESCRIP', descrip, comment='Short description of headerlet solution')
-    phdu.header.update('RMS_RA', rms_ra, comment='RMS in RA at ref pix of headerlet solution')
-    phdu.header.update('RMS_DEC', rms_dec, comment='RMS in Dec at ref pix of headerlet solution')
-    phdu.header.update('NMATCH', nmatch, comment='Number of sources used for headerlet solution')
-    phdu.header.update('CATALOG', catalog, comment='Astrometric catalog used for headerlet solution')
-    phdu.header.update('UPWCSVER', upwcsver.value, comment=upwcsver.comment)
-    phdu.header.update('PYWCSVER', pywcsver.value, comment=pywcsver.comment)
+    phdu.header['DATE'] = (time.strftime(fmt), 'Date FITS file was generated')
+    phdu.header['WCSNAME'] = (wcsname, 'WCS name')
+    phdu.header['DISTNAME'] = (distname, 'Distortion model name')
+    phdu.header['SIPNAME'] = (sipname,
+                              'origin of SIP polynomial distortion model')
+    phdu.header['NPOLFILE'] = (npolfile,
+                               'origin of non-polynmial distortion model')
+    phdu.header['D2IMFILE'] = (d2imfile,
+                               'origin of detector to image correction')
+    phdu.header['AUTHOR'] = (author, 'headerlet created by this user')
+    phdu.header['DESCRIP'] = (descrip,
+                              'Short description of headerlet solution')
+    phdu.header['RMS_RA'] = (rms_ra,
+                             'RMS in RA at ref pix of headerlet solution')
+    phdu.header['RMS_DEC'] = (rms_dec,
+                              'RMS in Dec at ref pix of headerlet solution')
+    phdu.header['NMATCH'] = (nmatch,
+                             'Number of sources used for headerlet solution')
+    phdu.header['CATALOG'] = (catalog,
+                              'Astrometric catalog used for headerlet '
+                              'solution')
+    phdu.header['UPWCSVER'] = (upwcsver.value, upwcsver.comment)
+    phdu.header['PYWCSVER'] = (pywcsver.value, pywcsver.comment)
 
     # clean up history string in order to remove whitespace characters that
     # would cause problems with FITS
@@ -777,7 +781,7 @@ def write_headerlet(filename, hdrname, output=None, sciext='SCI',
         if wcsname in [None, ' ', '', 'INDEF'] and wcskey is None:
             message = """\n
             No valid WCS found found in %s.
-            A valid value for either "wcsname" or "wcskey" 
+            A valid value for either "wcsname" or "wcskey"
             needs to be specified.
             """ % fname
             logger.critical(message)
@@ -816,7 +820,7 @@ def write_headerlet(filename, hdrname, output=None, sciext='SCI',
                                     descrip=descrip, history=history,
                                     nmatch=nmatch, catalog=catalog,
                                     logging=False)
-        
+
         if attach:
             # Check to see whether or not a HeaderletHDU with
             #this hdrname already exists
@@ -1050,12 +1054,12 @@ def create_headerlet(filename, sciext='SCI', hdrname=None, destim=None,
 
     # get the version of STWCS used to create the WCS of the science file.
     try:
-        upwcsver = fobj[0].header.ascard['UPWCSVER']
+        upwcsver = fobj[0].header.cards[fobj[0].header.index('UPWCSVER')]
     except KeyError:
         upwcsver = pyfits.Card("UPWCSVER", " ",
                                "Version of STWCS used to update the WCS")
     try:
-        pywcsver = fobj[0].header.ascard['PYWCSVER']
+        pywcsver = fobj[0].header.cards[fobj[0].header.index('PYWCSVER')]
     except KeyError:
         pywcsver = pyfits.Card("PYWCSVER", " ",
                                "Version of PYWCS used to update the WCS")
@@ -1121,42 +1125,36 @@ def create_headerlet(filename, sciext='SCI', hdrname=None, destim=None,
             if wcskey != ' ':
                 # Now read in specified linear WCS terms from alternate WCS
                 try:
-                    althdr = altwcs.convertAltWCS(fobj, fext, oldkey=wcskey, newkey=" ")
+                    althdr = altwcs.convertAltWCS(fobj, fext, oldkey=wcskey,
+                                                  newkey=" ")
                     althdrwcs = HSTWCS(fobj, fext, wcskey=wcskey)
                 except KeyError:
                     continue # Skip over any extension which does not have a WCS
-                althdr = althdr.ascard
                 # Update full WCS with values from alternate WCS
-                for card in althdr:
-                    h.update(card.key, card.value)
+                for keyword, value in althdr.items():
+                    h[keyword] = value
                 if hasattr(althdrwcs, 'orientat'):
-                    h.update('ORIENTAT', althdrwcs.orientat, comment=orient_comment)
-            h = h.ascard
-
+                    h['ORIENTAT'] = (althdrwcs.orientat, orient_comment)
             if hasattr(hwcs, 'vafactor'):
-                h.append(pyfits.Card(key='VAFACTOR', value=hwcs.vafactor,
-                                 comment='Velocity aberration plate scale factor'))
-            h.insert(0, pyfits.Card(key='EXTNAME', value='SIPWCS',
-                                    comment='Extension name'))
+                h.append(('VAFACTOR', hwcs.vafactor,
+                          'Velocity aberration plate scale factor'))
+            h.insert(0, ('EXTNAME', 'SIPWCS', 'Extension name'))
             if isinstance(fext, int):
                 if 'extver' in fobj[fext].header:
                     val = fobj[fext].header['extver']
                 else:
                     val = fext
             else: val = fext[1]
-            h.insert(1, pyfits.Card(key='EXTVER', value=val,
-                                    comment='Extension version'))
-            h.append(pyfits.Card(key="SCIEXT", value=e,
-                                 comment="Target science data extension"))
-            fhdr = fobj[fext].header.ascard
+            h.insert(1, ('EXTVER', val, 'Extension version'))
+            h.append(('SCIEXT', e, 'Target science data extension'))
+            fhdr = fobj[fext].header
             if npolfile is not 'NOMODEL':
                 cpdis = fhdr['CPDIS*...']
                 for c in range(1, len(cpdis) + 1):
                     h.append(cpdis[c - 1])
                     dp = fhdr['DP%s*...' % c]
-                    for kw in dp:
-                        dpval = kw.value
-                        if 'EXTVER' in kw.key:
+                    for kw, dpval in dp.items():
+                        if 'EXTVER' in kw:
                             wcsdvarr_extns.append(dpval)
                             break
 
@@ -1834,8 +1832,9 @@ class Headerlet(pyfits.HDUList):
 
         self.fit_kws = ['HDRNAME', 'NMATCH', 'CATALOG']
         self.history = ''
-        for card in self[0].header['HISTORY*']:
-            self.history += card.value+'\n'
+        # header['HISTORY'] returns an iterable of all HISTORY values
+        for hist in self[0].header['HISTORY']:
+            self.history += hist + '\n'
 
         self.d2imerr = 0
         self.axiscorr = 1
@@ -1985,7 +1984,7 @@ class Headerlet(pyfits.HDUList):
             numsip = countExtn(self, 'SIPWCS')
             for idx in range(1, numsip + 1):
                 fhdr = fobj[('SCI', idx)].header
-                siphdr = self[('SIPWCS', idx)].header.ascard
+                siphdr = self[('SIPWCS', idx)].header
 
                 if dist_models_equal:
                     hwcs = HSTWCS(fobj, ext=('SCI', idx))
@@ -2004,40 +2003,41 @@ class Headerlet(pyfits.HDUList):
                         bkeywd = 'HISTORY'
                 logger.debug(
                     "Updating WCS keywords after %s and/or before %s " %
-                    (akeywd,bkeywd))
+                    (akeywd, bkeywd))
                 update_cpdis = False
-                for k in siphdr[-1::-1]:
+                for c in siphdr.cards[-1::-1]:
                     # Replace or add WCS keyword from headerlet as PRIMARY WCS
                     # In the case that the distortion models are not equal,
                     # this will copy all keywords from headerlet into fobj
                     # When the distortion models are equal, though, it will
                     # only copy the primary WCS keywords (CRVAL,CRPIX,...)
-                    if (dist_models_equal and (k.key in hwcshdr)) or \
-                     (not dist_models_equal and k.key not in FITS_STD_KW):
+                    if ((dist_models_equal and (c.keyword in hwcshdr)) or
+                        (not dist_models_equal and
+                         c.keyword not in FITS_STD_KW)):
                         if 'DP' not in k.key:
-                            fhdr.update(k.key, k.value, comment=k.comment,
-                                        after=akeywd, before=bkeywd)
+                            fhdr.set(c.keyword, c.value, c.comment,
+                                     after=akeywd, before=bkeywd)
                         else:
                             update_cpdis = True
                     else:
                         pass
                 # Update WCS with optional CRDER (error) kws from headerlet
                 if 'crder1' in siphdr:
-                    for kw in siphdr['crder*']:
-                        fhdr.update(kw.key, kw.value, comment=kw.comment, 
-                                    after='WCSNAME')
+                    for card in siphdr['crder*'].cards:
+                        fhdr.set(card.keyword, card.value, card.comment,
+                                 after='WCSNAME')
 
                 # Update WCS with HDRNAME as well
                 for kw in self.fit_kws:
-                    fhdr.update(kw, self[0].header[kw], after='WCSNAME')
+                    fhdr.set(kw, self[0].header[kw], after='WCSNAME')
 
                 # Update header with record-valued keywords here
                 if update_cpdis:
                     numdp = len(siphdr['CPDIS*'])
                     for dpaxis in range(1, numdp+1):
-                        cpdis_indx = fhdr.ascard.index_of('CPDIS%d' % (dpaxis))
-                        for dpcard in siphdr['DP%d*' % (dpaxis)][-1::-1]:
-                            fhdr.ascard.insert(cpdis_indx, dpcard)
+                        cpdis_indx = fhdr.index('CPDIS%d' % (dpaxis))
+                        for dpcard in siphdr['DP%d*' % (dpaxis)][-1::-1].cards:
+                            fhdr.insert(cpdis_indx, dpcard)
 
             # Update the WCSCORR table with new rows from the headerlet's WCSs
             wcscorr.update_wcscorr(fobj, self, 'SIPWCS')
@@ -2094,7 +2094,7 @@ class Headerlet(pyfits.HDUList):
                     distname = self.build_distname(fobj)
                 except:
                     distname = 'UNKNOWN'
-                    
+
             if distname == 'UNKNOWN' or self.distname != distname:
                 message = """
                 Observation %s cannot be updated with headerlet %s
@@ -2144,32 +2144,33 @@ class Headerlet(pyfits.HDUList):
                 except ValueError:
                     sciext = fu.parseExtn(sciext)
                 fhdr = fobj[sciext].header
-                siphdr = self[('SIPWCS', idx)].header.ascard
+                siphdr = self[('SIPWCS', idx)].header
 
                 # a minimal attempt to get the position of the WCS keywords group
                 # in the header by looking for the PA_APER kw.
                 # at least make sure the WCS kw are written before the HISTORY kw
                 # if everything fails, append the kw to the header
                 try:
-                    wind = fhdr.ascard.index_of('HISTORY')
+                    wind = fhdr.index('HISTORY')
                 except KeyError:
                     wind = len(fhdr)
                 logger.debug("Inserting WCS keywords at index %s" % wind)
 
-                for k in siphdr:
+                for card in siphdr.cards:
                     for akw in altwcs.altwcskw:
-                        if akw in k.key:
-                            fhdr.ascard.insert(wind, pyfits.Card(
-                                            key=k.key[:7]+wkey, value=k.value,
-                                            comment=k.comment))
+                        if akw in card.keyword:
+                            fhdr.insert(wind,
+                                        pyfits.Card(card.keyword[:7] + wkey,
+                                                    value=card.value,
+                                                    comment=card.comment))
                     else:
                         pass
 
-                fhdr.ascard.insert(wind, pyfits.Card('WCSNAME'+wkey, wname))
+                fhdr.insert(wind, pyfits.Card('WCSNAME' + wkey, wname))
                 # also update with HDRNAME (a non-WCS-standard kw)
                 for kw in self.fit_kws:
-                    fhdr.ascard.insert(wind, pyfits.Card(kw+wkey,
-                                        self[0].header[kw]))
+                    fhdr.insert(wind, pyfits.Card(kw + wkey,
+                                                  self[0].header[kw]))
             # Update the WCSCORR table with new rows from the headerlet's WCSs
             wcscorr.update_wcscorr(fobj, self, 'SIPWCS')
 
@@ -2322,11 +2323,11 @@ class Headerlet(pyfits.HDUList):
         return unique
 
     def verify_model(self, dest):
-        """ 
+        """
         Verifies that the headerlet can be applied to the observation
-        
+
         Determines whether or not the file specifies the same distortion
-        model/reference files.  
+        model/reference files.
         """
         destim_opened = False
         if not isinstance(dest, pyfits.HDUList):
@@ -2334,8 +2335,8 @@ class Headerlet(pyfits.HDUList):
             destim_opened = True
         else:
             destim = dest
-            
-        if 'distname' in destim[0].header:    
+
+        if 'distname' in destim[0].header:
             dname = destim[0].header['DISTNAME']
         else:
             dname = self.build_distname(dest)
@@ -2345,7 +2346,7 @@ class Headerlet(pyfits.HDUList):
             return True
         else:
             return False
-        
+
     def verify_dest(self, dest):
         """
         verifies that the headerlet can be applied to the observation
@@ -2371,14 +2372,14 @@ class Headerlet(pyfits.HDUList):
 
     def build_distname(self, dest):
         """
-        Builds the DISTNAME for dest based on reference file names. 
+        Builds the DISTNAME for dest based on reference file names.
         """
         sipname = utils.build_sipname(dest)
         npolname = utils.build_npolname(dest)
         d2imname = utils.build_d2imname(dest)
         dname = utils.build_distname(sipname,npolname,d2imname)
         return dname
-    
+
     def tofile(self, fname, destim=None, hdrname=None, clobber=False):
         """
         Write this headerlet to a file
@@ -2417,7 +2418,7 @@ class Headerlet(pyfits.HDUList):
                 self._remove_idc_coeffs(dest[idx])
                 self._remove_fit_values(dest[idx])
                 try:
-                    del dest[idx].header.ascard['VAFACTOR']
+                    del dest[idx].header['VAFACTOR']
                 except KeyError:
                     pass
 
@@ -2437,7 +2438,7 @@ class Headerlet(pyfits.HDUList):
         refkw = ['IDCTAB', 'NPOLFILE', 'D2IMFILE']
         for kw in refkw:
             try:
-                del phdu.header.ascard[kw]
+                del phdu.header[kw]
             except KeyError:
                 pass
 
@@ -2495,7 +2496,7 @@ class Headerlet(pyfits.HDUList):
         try:
             for c in range(1, len(cpdis) + 1):
                 del ext.header['DP%s*...' % c]
-                del ext.header[cpdis[c - 1].key]
+                del ext.header[cpdis.cards[c - 1].keyword]
             del ext.header['CPERR*']
             del ext.header['NPOLFILE']
             del ext.header['NPOLEXT']
@@ -2538,15 +2539,15 @@ class Headerlet(pyfits.HDUList):
 
         hdr_logger.debug("Removing Primary WCS from (%s, %s)"
                      % (ext.name, ext._extver))
-        naxis = ext.header.ascard['NAXIS'].value
+        naxis = ext.header['NAXIS']
         for key in basic_wcs:
             for i in range(1, naxis + 1):
                 try:
-                    del ext.header.ascard[key + str(i)]
+                    del ext.header[key + str(i)]
                 except KeyError:
                     pass
         try:
-            del ext.header.ascard['WCSAXES']
+            del ext.header['WCSAXES']
         except KeyError:
             pass
 
@@ -2560,7 +2561,7 @@ class Headerlet(pyfits.HDUList):
         coeffs = ['OCX10', 'OCX11', 'OCY10', 'OCY11', 'IDCSCALE']
         for k in coeffs:
             try:
-                del ext.header.ascard[k]
+                del ext.header[k]
             except KeyError:
                 pass
 
@@ -2628,19 +2629,19 @@ class HeaderletHDU(pyfits.hdu.nonstandard.FitsHDU):
         else:
             sipname = phdu.header['WCSNAME']
 
-        hlet.header.update('HDRNAME', phdu.header['HDRNAME'],
-                           phdu.header.ascard['HDRNAME'].comment)
-        hlet.header.update('DATE', phdu.header['DATE'],
-                           phdu.header.ascard['DATE'].comment)
-        hlet.header.update('SIPNAME', sipname, 'SIP distortion model name')
-        hlet.header.update('WCSNAME', phdu.header['WCSNAME'], 'WCS name'),
-        hlet.header.update('DISTNAME', phdu.header['DISTNAME'],
-                           'Distortion model name'),
-        hlet.header.update('NPOLFILE', phdu.header['NPOLFILE'],
-                           phdu.header.ascard['NPOLFILE'].comment)
-        hlet.header.update('D2IMFILE', phdu.header['D2IMFILE'],
-                           phdu.header.ascard['D2IMFILE'].comment)
-        hlet.header.update('EXTNAME', cls._extension, 'Extension name')
+        hlet.header['HDRNAME'] = (phdu.header['HDRNAME'],
+                                  phdu.header.comments['HDRNAME'])
+        hlet.header['DATE'] = (phdu.header['DATE'],
+                               phdu.header.comments['DATE'])
+        hlet.header['SIPNAME'] = (sipname, 'SIP distortion model name')
+        hlet.header['WCSNAME'] = (phdu.header['WCSNAME'], 'WCS name'),
+        hlet.header['DISTNAME'] = (phdu.header['DISTNAME'],
+                                   'Distortion model name'),
+        hlet.header['NPOLFILE'] = (phdu.header['NPOLFILE'],
+                                   phdu.header.comments['NPOLFILE'])
+        hlet.header['D2IMFILE'] = (phdu.header['D2IMFILE'],
+                                   phdu.header.comments['D2IMFILE'])
+        hlet.header['EXTNAME'] = (cls._extension, 'Extension name')
 
         return hlet
 
diff --git a/lib/stwcs/wcsutil/hstwcs.py b/lib/stwcs/wcsutil/hstwcs.py
index d138f08..371de0f 100644
--- a/lib/stwcs/wcsutil/hstwcs.py
+++ b/lib/stwcs/wcsutil/hstwcs.py
@@ -40,7 +40,7 @@ def extract_rootname(kwvalue,suffix=""):
         fullval = kwvalue
     # Extract filename without path from kwvalue
     fname = os.path.basename(fullval).strip()
-    
+
     # Now, rip out just the rootname from the full filename
     rootname = fileutil.buildNewRootname(fname)
 
@@ -54,7 +54,7 @@ def build_default_wcsname(idctab):
     wcsname = 'IDC_' + idcname
     return wcsname
 
-# 
+#
 #### HSTWCS Class definition
 #
 class HSTWCS(WCS):
@@ -173,7 +173,7 @@ class HSTWCS(WCS):
             to a CD matrix, if reasonable, by running pc2.cd() method.\n \
             The plate scale can be set then by calling setPscale() method.\n"
             self.pscale = None
-    
+
     def setOrient(self):
         """
         Computes ORIENTAT from the CD matrix
@@ -278,7 +278,7 @@ class HSTWCS(WCS):
                     chip=self.chip, direction='forward', date=self.date_obs,
                     filter1=self.filter1, filter2=self.filter2,
                     offtab=self.offtab, binned=self.binned)
-        
+
         if self.ltv1 != 0. or self.ltv2 != 0.:
             self.resetLTV()
 
@@ -287,26 +287,26 @@ class HSTWCS(WCS):
                 print 'Update header with IDC model kw requested but header was not provided\n.'
             else:
                 self._updatehdr(header)
-    
+
     def resetLTV(self):
         """
         Reset LTV values for polarizer data
-        
-        The polarizer field is smaller than the detector field. 
-        The distortion coefficients are defined for the entire 
-        polarizer field and the LTV values are set as with subarray 
+
+        The polarizer field is smaller than the detector field.
+        The distortion coefficients are defined for the entire
+        polarizer field and the LTV values are set as with subarray
         data. This may also be true for other special filters.
-        This is a special case when the observation is considered 
-        a subarray in terms of detector field but a full frame in 
+        This is a special case when the observation is considered
+        a subarray in terms of detector field but a full frame in
         terms of distortion model.
-        To avoid shifting the distortion coefficients the LTV values 
+        To avoid shifting the distortion coefficients the LTV values
         are reset to 0.
         """
         if self.naxis1 == self.idcmodel.refpix['XSIZE'] and  \
            self.naxis2 == self.idcmodel.refpix['YSIZE']:
             self.ltv1 = 0.
             self.ltv2 = 0.
-            
+
     def wcs2header(self, sip2hdr=False, idc2hdr=True):
         """
         Create a pyfits.Header object from WCS keywords.
@@ -329,13 +329,13 @@ class HSTWCS(WCS):
             else:
                 wname = 'DEFAULT'
             h.update('wcsname',value=wname)
-            
+
         if idc2hdr:
             for card in self._idc2hdr():
                 h.update(card.key,value=card.value,comment=card.comment)
         try:
-            del h.ascard['RESTFRQ']
-            del h.ascard['RESTWAV']
+            del h['RESTFRQ']
+            del h['RESTWAV']
         except KeyError: pass
 
         if sip2hdr and self.sip:
diff --git a/lib/stwcs/wcsutil/instruments.py b/lib/stwcs/wcsutil/instruments.py
index 997bdc8..8641e51 100644
--- a/lib/stwcs/wcsutil/instruments.py
+++ b/lib/stwcs/wcsutil/instruments.py
@@ -1,8 +1,7 @@
 from __future__ import division # confidence high
 
-import pyfits
 from mappings import ins_spec_kw
-    
+
 class InstrWCS(object):
     """
     A base class for instrument specific keyword definition.
@@ -10,15 +9,15 @@ class InstrWCS(object):
     all set_kw methods.
     """
     def __init__(self, hdr0=None, hdr=None):
-        self.exthdr = hdr   
+        self.exthdr = hdr
         self.primhdr = hdr0
         self.set_ins_spec_kw()
-        
+
     def set_ins_spec_kw(self):
         """
         This method MUST call all set_kw methods.
-        There should be a set_kw method for all kw listed in 
-        mappings.ins_spec_kw. TypeError handles the case when 
+        There should be a set_kw method for all kw listed in
+        mappings.ins_spec_kw. TypeError handles the case when
         fobj='DEFAULT'.
         """
         self.set_idctab()
@@ -38,13 +37,13 @@ class InstrWCS(object):
         self.set_binned()
         self.set_chip()
         self.set_parity()
-        
+
     def set_idctab(self):
         try:
             self.idctab = self.primhdr['IDCTAB']
         except (KeyError, TypeError):
             self.idctab = None
-            
+
     def set_offtab(self):
         try:
             self.offtab = self.primhdr['OFFTAB']
@@ -56,13 +55,13 @@ class InstrWCS(object):
             self.date_obs = self.primhdr['DATE-OBS']
         except (KeyError, TypeError):
             self.date_obs = None
-            
+
     def set_ra_targ(self):
         try:
             self.ra_targ = self.primhdr['RA-TARG']
         except (KeyError, TypeError):
             self.ra_targ = None
-    
+
     def set_dec_targ(self):
         try:
             self.dec_targ = self.primhdr['DEC-TARG']
@@ -74,25 +73,25 @@ class InstrWCS(object):
             self.pav3 = self.primhdr['PA_V3']
         except (KeyError, TypeError):
             self.pav3 = None
-            
+
     def set_filter1(self):
         try:
             self.filter1 = self.primhdr['FILTER1']
         except (KeyError, TypeError):
             self.filter1 = None
-            
+
     def set_filter2(self):
         try:
             self.filter2 = self.primhdr['FILTER2']
         except (KeyError, TypeError):
             self.filter2 = None
-            
-    def set_vafactor(self): 
+
+    def set_vafactor(self):
         try:
             self.vafactor = self.exthdr['VAFACTOR']
         except (KeyError, TypeError):
             self.vafactor = 1
-            
+
     def set_naxis1(self):
         try:
             self.naxis1 = self.exthdr['naxis1']
@@ -101,7 +100,7 @@ class InstrWCS(object):
                 self.naxis1 = self.exthdr['npix1']
             except (KeyError, TypeError):
                 self.naxis1 = None
-                
+
     def set_naxis2(self):
         try:
             self.naxis2 = self.exthdr['naxis2']
@@ -110,69 +109,69 @@ class InstrWCS(object):
                 self.naxis2 = self.exthdr['npix2']
             except (KeyError, TypeError):
                 self.naxis2 = None
-                
+
     def set_ltv1(self):
         try:
             self.ltv1 = self.exthdr['LTV1']
         except (KeyError, TypeError):
             self.ltv1 = 0.0
-        
+
     def set_ltv2(self):
         try:
             self.ltv2 = self.exthdr['LTV2']
         except (KeyError, TypeError):
             self.ltv2 = 0.0
-            
+
     def set_binned(self):
         try:
             self.binned = self.exthdr['BINAXIS1']
         except (KeyError, TypeError):
             self.binned = 1
-        
+
     def set_chip(self):
         try:
             self.chip = self.exthdr['CCDCHIP']
         except (KeyError, TypeError):
             self.chip = 1
-                  
+
     def set_parity(self):
         self.parity = [[1.0,0.0],[0.0,-1.0]]
-    
+
     def set_detector(self):
-        # each instrument has a different kw for detector and it can be 
-        # in a different header, so this is to be handled by the instrument classes 
+        # each instrument has a different kw for detector and it can be
+        # in a different header, so this is to be handled by the instrument classes
         self.detector = 'DEFAULT'
-        
+
 class ACSWCS(InstrWCS):
     """
-    get instrument specific kw    
+    get instrument specific kw
     """
-    
+
     def __init__(self, hdr0, hdr):
         self.primhdr = hdr0
         self.exthdr = hdr
         InstrWCS.__init__(self,hdr0, hdr)
         self.set_ins_spec_kw()
-        
+
     def set_detector(self):
         try:
-            self.detector = self.primhdr['DETECTOR']  
+            self.detector = self.primhdr['DETECTOR']
         except KeyError:
             print 'ERROR: Detector kw not found.\n'
             raise
-        
+
     def set_parity(self):
         parity = {'WFC':[[1.0,0.0],[0.0,-1.0]],
                 'HRC':[[-1.0,0.0],[0.0,1.0]],
                 'SBC':[[-1.0,0.0],[0.0,1.0]]}
-        
+
         if self.detector not in parity.keys():
             parity = InstrWCS.set_parity(self)
         else:
             self.parity = parity[self.detector]
-    
-        
-class WFPC2WCS(InstrWCS):   
+
+
+class WFPC2WCS(InstrWCS):
 
 
     def __init__(self, hdr0, hdr):
@@ -180,7 +179,7 @@ class WFPC2WCS(InstrWCS):
         self.exthdr = hdr
         InstrWCS.__init__(self,hdr0, hdr)
         self.set_ins_spec_kw()
-    
+
     def set_filter1(self):
         self.filter1 = self.primhdr.get('FILTNAM1', None)
         if self.filter1 == " " or self.filter1 == None:
@@ -190,8 +189,8 @@ class WFPC2WCS(InstrWCS):
         self.filter2 = self.primhdr.get('FILTNAM2', None)
         if self.filter2 == " " or self.filter2 == None:
             self.filter2 = 'CLEAR2'
-            
-    
+
+
     def set_binned(self):
         mode = self.primhdr.get('MODE', 1)
         if mode == 'FULL':
@@ -201,68 +200,68 @@ class WFPC2WCS(InstrWCS):
 
     def set_chip(self):
         self.chip = self.exthdr.get('DETECTOR', 1)
-    
+
     def set_parity(self):
         self.parity = [[-1.0,0.],[0.,1.0]]
-        
+
     def set_detector(self):
         try:
             self.detector = self.exthdr['DETECTOR']
         except KeyError:
             print 'ERROR: Detector kw not found.\n'
             raise
-    
+
 
 class WFC3WCS(InstrWCS):
     """
     Create a WFC3 detector specific class
     """
-    
+
     def __init__(self, hdr0, hdr):
         self.primhdr = hdr0
         self.exthdr = hdr
         InstrWCS.__init__(self,hdr0, hdr)
         self.set_ins_spec_kw()
-    
+
     def set_detector(self):
         try:
-            self.detector = self.primhdr['DETECTOR']  
+            self.detector = self.primhdr['DETECTOR']
         except KeyError:
             print 'ERROR: Detector kw not found.\n'
             raise
-        
+
     def set_filter1(self):
         self.filter1 = self.primhdr.get('FILTER', None)
         if self.filter1 == " " or self.filter1 == None:
             self.filter1 = 'CLEAR'
-    
+
     def set_filter2(self):
         #Nicmos idc tables do not allow 2 filters.
         self.filter2 = 'CLEAR'
-        
+
     def set_parity(self):
-        parity = {'UVIS':[[-1.0,0.0],[0.0,1.0]], 
+        parity = {'UVIS':[[-1.0,0.0],[0.0,1.0]],
           'IR':[[-1.0,0.0],[0.0,1.0]]}
-        
+
         if self.detector not in parity.keys():
             parity = InstrWCS.set_parity(self)
         else:
             self.parity = parity[self.detector]
-            
+
 class NICMOSWCS(InstrWCS):
     """
     Create a NICMOS specific class
     """
-    
+
     def __init__(self, hdr0, hdr):
         self.primhdr = hdr0
         self.exthdr = hdr
         InstrWCS.__init__(self,hdr0, hdr)
         self.set_ins_spec_kw()
-    
+
     def set_parity(self):
         self.parity = [[-1.0,0.],[0.,1.0]]
-        
+
     def set_filter1(self):
         self.filter1 = self.primhdr.get('FILTER', None)
         if self.filter1 == " " or self.filter1 == None:
@@ -271,31 +270,31 @@ class NICMOSWCS(InstrWCS):
     def set_filter2(self):
         #Nicmos idc tables do not allow 2 filters.
         self.filter2 = 'CLEAR'
-        
+
     def set_chip(self):
         self.chip = self.detector
-            
+
     def set_detector(self):
         try:
-            self.detector = self.primhdr['CAMERA']  
+            self.detector = self.primhdr['CAMERA']
         except KeyError:
             print 'ERROR: Detector kw not found.\n'
             raise
-    
+
 class STISWCS(InstrWCS):
     """
     A STIS specific class
     """
-    
+
     def __init__(self, hdr0, hdr):
         self.primhdr = hdr0
         self.exthdr = hdr
         InstrWCS.__init__(self,hdr0, hdr)
         self.set_ins_spec_kw()
-        
+
     def set_parity(self):
         self.parity = [[-1.0,0.],[0.,1.0]]
-        
+
     def set_filter1(self):
         self.filter1 = self.exthdr.get('OPT_ELEM', None)
         if self.filter1 == " " or self.filter1 == None:
@@ -305,17 +304,17 @@ class STISWCS(InstrWCS):
         self.filter2 = self.exthdr.get('FILTER', None)
         if self.filter2 == " " or self.filter2 == None:
             self.filter2 = 'CLEAR2'
-            
+
     def set_detector(self):
         try:
-            self.detector = self.primhdr['DETECTOR']  
+            self.detector = self.primhdr['DETECTOR']
         except KeyError:
             print 'ERROR: Detector kw not found.\n'
             raise
-        
+
     def set_date_obs(self):
         try:
             self.date_obs = self.exthdr['DATE-OBS']
         except (KeyError, TypeError):
             self.date_obs = None
-    
\ No newline at end of file
+