diff options
Diffstat (limited to 'wcsutil/__init__.py')
| -rw-r--r-- | wcsutil/__init__.py | 75 |
1 files changed, 46 insertions, 29 deletions
diff --git a/wcsutil/__init__.py b/wcsutil/__init__.py index 7e87fa6..5bdbeb9 100644 --- a/wcsutil/__init__.py +++ b/wcsutil/__init__.py @@ -5,6 +5,7 @@ from pywcs import WCS import pyfits import instruments from stwcs.distortion import models, coeff_converter +from stwcs import utils import numpy as np from pytools import fileutil from pytools.fileutil import DEGTORAD, RADTODEG @@ -22,11 +23,11 @@ class HSTWCS(WCS): Purpose ======= Create a WCS object based on the instrument. - It has all basic WCS kw as attribbutes (set by pywcs). + It has all basic WCS kw as attributes (set by pywcs). It also uses the primary and extension header to define instrument specific attributes. """ - def __init__(self, fobj='DEFAULT', ext=None, minerr=0.0): + def __init__(self, fobj='DEFAULT', ext=None, minerr=0.0, wcskey=" "): """ :Parameters: `fobj`: string or PyFITS HDUList object or None @@ -45,13 +46,14 @@ class HSTWCS(WCS): self.inst_kw = ins_spec_kw self.minerr = minerr + self.wcskey = wcskey if fobj != 'DEFAULT': filename, hdr0, ehdr, phdu = self.parseInput(f=fobj, ext=ext) self.filename = filename self.instrument = hdr0['INSTRUME'] - WCS.__init__(self, ehdr, fobj=phdu, minerr=minerr) + WCS.__init__(self, ehdr, fobj=phdu, minerr=self.minerr, key=self.wcskey) # If input was a pyfits HDUList object, it's the user's # responsibility to close it, otherwise, it's closed here. if not isinstance(fobj, pyfits.HDUList): @@ -65,7 +67,7 @@ class HSTWCS(WCS): else: # create a default HSTWCS object self.instrument = 'DEFAULT' - WCS.__init__(self, minerr=minerr) + WCS.__init__(self, minerr=self.minerr, key=self.wcskey) self.wcs.cd = np.array([[1.0, 0.0], [0.0, 1.0]], np.double) self.wcs.crval = np.zeros((self.naxis,), np.double) self.wcs.crpix = np.zeros((self.naxis,), np.double) @@ -260,37 +262,52 @@ class HSTWCS(WCS): self._updatehdr(header) - def restore(self, header=None): + def restore(self, header, wcskey): """ - Restore a WCS archive in memory and update the WCS object. - Restored are the basic WCS kw as well as pscale and orient. + If WCS with wcskey exists - read it in and update the primary WCS. + If not, keep the original primary WCS. """ from pywcs import Wcsprm - backup = {} - if header == None: - print 'Need a valid header in order to restore archive\n' - return - - for k in basic_wcs: - try: - nkw = ('O'+k)[:7] - backup[k] = header[nkw] - except KeyError: - pass - if backup == {}: - print 'No archive was found\n' - return - cdl=pyfits.CardList() - for item in backup.items(): - card = pyfits.Card(key=item[0], value=item[1]) - cdl.append(card) - - h = pyfits.Header(cdl) - wprm = Wcsprm(repr(h.ascard)) + try: + wprm = Wcsprm(repr(header.ascard), key=wcskey) + except KeyError: + print "Could not restore WCS with key %s" % wcskey + return self.wcs = wprm self.setPscale() self.setOrient() - + + def copyWCS(self, header=None, wcskey=None, wcsname=" ", clobber=True): + """ + Copy the current primary WCS as an alternate WCS + using wcskey and WCSNAME. If wcskey = " ", it overwrites the + primary WCS. + """ + assert isinstance(header, pyfits.Header) + assert len(wcskey) == 1 + #if wcskey == " ": wcskey = None + if header and not wcskey: + print "Please provide a valid wcskey for this WCS" + if wcskey not in utils.available_wcskeys(header) and not clobber: + print 'wcskey %s is already used in this header.' % wcskey + print 'Use "utils.next_wcskey" to obtain a valid wcskey' + hwcs = self.to_header() + wkey = 'WCSNAME' + wcskey + header.update(key=wkey, value=wcsname) + if self.wcs.has_pc(): + for c in ['CD1_1', 'CD1_2', 'CD2_1', 'CD2_2']: + del hwcs[c] + elif self.wcs.has_cd(): + for c in ['1_1', '1_2', '2_1', '2_2']: + hwcs.update(key='CD'+c, value=hwcs['PC'+c]) + del hwcs['PC'+c] + for k in hwcs.keys(): + key = k+wcskey + header.update(key=key, value = hwcs[k]) + norient = np.rad2deg(np.arctan2(hwcs['CD1_2'],hwcs['CD2_2'])) + okey = 'ORIENT%s' % wcskey + header.update(key=okey, value=norient) + def _updatehdr(self, ext_hdr): #kw2add : OCX10, OCX11, OCY10, OCY11 # record the model in the header for use by pydrizzle |