Merging changes from 'stwcs_hdrlet' branch (r18787 - r13909) into trunk. This version of STWCS (0.9.1) provides support for headerlets based on 'Headerlet Design' wiki document, and includes TEAL interfaces for all public headerlet functions. It also moves the TEAL interface for 'updatewcs' from 'astrodither' to this package. The TEAL interaces have been included as a new 'gui' sub-package in order to keep them separate from the remainder of the package's functionality.

git-svn-id: http://svn.stsci.edu/svn/ssb/stsci_python/stsci_python/trunk/stwcs@13910 fe389314-cf27-0410-b35b-8c050e845b92

1 files changed, 97 insertions, 29 deletions

diff --git a/lib/stwcs/wcsutil/altwcs.py b/lib/stwcs/wcsutil/altwcs.py
index 1f6dc01..4f25abb 100644
--- a/lib/stwcs/wcsutil/altwcs.py
+++ b/lib/stwcs/wcsutil/altwcs.py
@@ -9,6 +9,7 @@ from stsci.tools import fileutil as fu
 
 altwcskw = ['WCSAXES', 'CRVAL', 'CRPIX', 'PC', 'CDELT', 'CD', 'CTYPE', 'CUNIT',
             'PV', 'PS']
+altwcskw_extra = ['LATPOLE','LONPOLE','RESTWAV','RESTFRQ']
 
 # file operations
 def archiveWCS(fname, ext=None, wcskey=" ", wcsname=" ", reusekey=False):
@@ -98,24 +99,23 @@ def archiveWCS(fname, ext=None, wcskey=" ", wcsname=" ", reusekey=False):
                 choose another wcsname." %wcsname)
         else:
             wkey = next_wcskey(f[wcsext].header)
-            wname = wcsname
+            if wcsname.strip():
+                wname = wcsname
+            else:
+                # determine which WCSNAME needs to be replicated in archived WCS
+                wname = wcsnames(f[wcsext].header)[' ']
     else:
         wkey = wcskey
         wname = wcsname
     
     for e in ext:
-        try:
-            w = pywcs.WCS(f[e].header, fobj=f)
-        except:
-            # this should be revisited, should catch specific  errors
-            # KeyError - not a valid key, ValueError - not a valid extension, etc
+        hwcs = readAltWCS(f,e,wcskey=' ')
+        if hwcs is None:
             continue
-        hwcs = w.to_header()
+
         wcsnamekey = 'WCSNAME' + wkey
         f[e].header.update(key=wcsnamekey, value=wname)
-        
-        if w.wcs.has_cd():
-            pc2cd(hwcs)
+
         try:
             old_wcsname=hwcs.pop('WCSNAME')
         except:
@@ -276,17 +276,13 @@ def deleteWCS(fname, ext=None, wcskey=" ", wcsname=" "):
             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
-        try:
-            w = pywcs.WCS(hdr, fobj, key=wkey)
-        except KeyError:
+        hwcs = readAltWCs(fobj,i,wcskey=wkey)
+        if hwcs is None:
             continue
-        hwcs = w.to_header()
-        if w.wcs.has_cd():
-            pc2cd(hwcs, key=wkey)
         for k in hwcs.keys():
             del hdr[k]
             #del hdr['ORIENT'+wkey]
@@ -323,17 +319,11 @@ def _restore(fobj, ukey, fromextnum, toextnum=None, fromextnam=None, toextnam=No
             toextension =toextnum
     else:
         toextension = fromextension
-        
-    try:
-        nwcs = pywcs.WCS(fobj[fromextension].header, fobj=fobj, key=ukey)
-    except KeyError:
-        print 'restoreWCS: Could not read WCS with key %s' %ukey 
-        print '            Skipping %s[%s]' % (fobj.filename(), str(fromextension))
+
+    hwcs = readAltWCS(fobj,fromextension,wcskey=ukey,verbose=True)
+    if hwcs is None:
         return
-    hwcs = nwcs.to_header()
 
-    if nwcs.wcs.has_cd():
-        pc2cd(hwcs, key=ukey)
     for k in hwcs.keys():
         key = k[:-1]
         if key in fobj[toextension].header.keys():
@@ -367,6 +357,77 @@ def _getheader(fobj, ext):
         hdr = fobj[ext].header
     return hdr
         
+def readAltWCS(fobj, ext, wcskey=' ',verbose=False):
+    """ Reads in alternate WCS from specified extension
+
+    Parameters
+    ----------
+    fobj: string, pyfits.HDUList
+        fits filename or pyfits file object
+        containing alternate/primary WCS(s) to be converted
+    wcskey: string [" ",A-Z]
+        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)
+
+    hdr = _getheader(fobj,ext)
+    try:
+        nwcs = pywcs.WCS(hdr, fobj=fobj, key=wcskey)
+    except KeyError:
+        if verbose:
+            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 
+    another key.
+    
+    Parameters
+    ----------
+    fobj: string, pyfits.HDUList, 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 
+    
+    Returns
+    -------
+    hdr: pyfits.Header
+        header object with keywords renamed from oldkey to newkey
+    """
+    hdr = readAltWCS(fobj,ext,wcskey=oldkey)
+    if hdr is None:
+        return None
+    # Converting WCS to new key
+    for card in hdr:
+        if oldkey == ' ' or oldkey == '':
+            cname = card
+        else:
+            cname = card.rstrip(oldkey)
+        hdr.rename_key(card,cname+newkey,force=True)
+
+    return hdr
+
 def wcskeys(fobj, ext=None):
     """
     Returns a list of characters used in the header for alternate
@@ -383,7 +444,12 @@ def wcskeys(fobj, ext=None):
     _check_headerpars(fobj, ext)
     hdr = _getheader(fobj, ext)
     names = hdr["WCSNAME*"]
-    return [key.split('WCSNAME')[1].upper() for key in names.keys()]
+    d = []
+    for key in names.keys():
+        wkey = key.replace('WCSNAME','')
+        if wkey == '': wkey = ' '
+        d.append(wkey)
+    return d
 
 def wcsnames(fobj, ext=None):
     """
@@ -403,7 +469,9 @@ def wcsnames(fobj, ext=None):
     names = hdr["WCSNAME*"]
     d = {}
     for c in names:
-        d[c.key[-1]] = c.value
+        wkey = c.key.replace('WCSNAME','')
+        if wkey == '': wkey = ' '
+        d[wkey] = c.value
     return d
 
 def available_wcskeys(fobj, ext=None):
@@ -425,7 +493,7 @@ def available_wcskeys(fobj, ext=None):
     all_keys = list(string.ascii_uppercase)
     used_keys = wcskeys(hdr)
     try:
-        used_keys.remove("")
+        used_keys.remove(" ")
     except ValueError:
         pass
     [all_keys.remove(key) for key in used_keys]