restructure and add stwcs tests

1 files changed, 123 insertions, 0 deletions

diff --git a/stwcs/updatewcs/wfpc2_dgeo.py b/stwcs/updatewcs/wfpc2_dgeo.py
new file mode 100644
index 0000000..e57bb5c
--- /dev/null
+++ b/stwcs/updatewcs/wfpc2_dgeo.py
@@ -0,0 +1,123 @@
+""" wfpc2_dgeo - Functions to convert WFPC2 DGEOFILE into D2IMFILE
+
+"""
+import os
+import datetime
+
+import astropy
+from astropy.io import fits
+import numpy as np
+
+from stsci.tools import fileutil
+
+import logging
+logger = logging.getLogger("stwcs.updatewcs.apply_corrections")
+
+def update_wfpc2_d2geofile(filename, fhdu=None):
+    """
+    Creates a D2IMFILE from the DGEOFILE for a WFPC2 image (input), and
+    modifies the header to reflect the new usage.
+
+    Parameters
+    ----------
+    filename: string
+        Name of WFPC2 file to be processed.  This file will be updated
+        to delete any reference to a DGEOFILE and add a D2IMFILE to replace
+        that correction when running updatewcs.
+    fhdu: object
+        FITS object for WFPC2 image.  If user has already opened the WFPC2
+        file, they can simply pass that FITS object in for direct processing.
+
+    Returns
+    -------
+    d2imfile: string
+        Name of D2IMFILE created from DGEOFILE.  The D2IMFILE keyword in the
+        image header will be updated/added to point to this newly created file.
+
+    """
+    
+    close_fhdu = False
+    if fhdu is None:
+        fhdu = fileutil.openImage(filename, mode='update')
+        close_fhdu = True
+
+    dgeofile = fhdu['PRIMARY'].header.get('DGEOFILE', None)
+    already_converted = dgeofile not in [None, "N/A", "", " "]
+    if already_converted or 'ODGEOFIL' in fhdu['PRIMARY'].header:
+        if not already_converted:
+            dgeofile = fhdu['PRIMARY'].header.get('ODGEOFIL', None)
+        logger.info('Converting DGEOFILE %s into D2IMFILE...' % dgeofile)
+        rootname = filename[:filename.find('.fits')]
+        d2imfile = convert_dgeo_to_d2im(dgeofile,rootname)
+        fhdu['PRIMARY'].header['ODGEOFIL'] = dgeofile
+        fhdu['PRIMARY'].header['DGEOFILE'] = 'N/A'
+        fhdu['PRIMARY'].header['D2IMFILE'] = d2imfile
+    else:
+        d2imfile = None
+        fhdu['PRIMARY'].header['DGEOFILE'] = 'N/A'
+        if 'D2IMFILE' not in fhdu['PRIMARY'].header:
+            fhdu['PRIMARY'].header['D2IMFILE'] = 'N/A'
+
+    # Only close the file handle if opened in this function
+    if close_fhdu:
+        fhdu.close()
+
+    # return the d2imfile name so that calling routine can keep
+    # track of the new file created and delete it later if necessary
+    # (multidrizzle clean=True mode of operation)
+    return d2imfile
+
+def convert_dgeo_to_d2im(dgeofile,output,clobber=True):
+    """ Routine that converts the WFPC2 DGEOFILE into a D2IMFILE.
+    """
+    dgeo = fileutil.openImage(dgeofile)
+    outname = output+'_d2im.fits'
+
+    removeFileSafely(outname)
+    data = np.array([dgeo['dy',1].data[:,0]])
+    scihdu = fits.ImageHDU(data=data)
+    dgeo.close()
+    # add required keywords for D2IM header
+    scihdu.header['EXTNAME'] = ('DY', 'Extension name')
+    scihdu.header['EXTVER'] = (1, 'Extension version')
+    fits_str = 'PYFITS Version '+str(astropy.__version__)
+    scihdu.header['ORIGIN'] = (fits_str, 'FITS file originator')
+    scihdu.header['INHERIT'] = (False, 'Inherits global header')
+
+    dnow = datetime.datetime.now()
+    scihdu.header['DATE'] = (str(dnow).replace(' ','T'),
+                             'Date FITS file was generated')
+
+    scihdu.header['CRPIX1'] = (0, 'Distortion array reference pixel')
+    scihdu.header['CDELT1'] = (1, 'Grid step size in first coordinate')
+    scihdu.header['CRVAL1'] = (0, 'Image array pixel coordinate')
+    scihdu.header['CRPIX2'] = (0, 'Distortion array reference pixel')
+    scihdu.header['CDELT2'] = (1, 'Grid step size in second coordinate')
+    scihdu.header['CRVAL2'] = (0, 'Image array pixel coordinate')
+
+    phdu = fits.PrimaryHDU()
+    phdu.header['INSTRUME'] = 'WFPC2'
+    d2imhdu = fits.HDUList()
+    d2imhdu.append(phdu)
+    scihdu.header['DETECTOR'] = (1, 'CCD number of the detector: PC 1, WFC 2-4 ')
+    d2imhdu.append(scihdu.copy())
+    scihdu.header['EXTVER'] = (2, 'Extension version')
+    scihdu.header['DETECTOR'] = (2, 'CCD number of the detector: PC 1, WFC 2-4 ')
+    d2imhdu.append(scihdu.copy())
+    scihdu.header['EXTVER'] = (3, 'Extension version')
+    scihdu.header['DETECTOR'] = (3, 'CCD number of the detector: PC 1, WFC 2-4 ')
+    d2imhdu.append(scihdu.copy())
+    scihdu.header['EXTVER'] = (4, 'Extension version')
+    scihdu.header['DETECTOR'] = (4, 'CCD number of the detector: PC 1, WFC 2-4 ')
+    d2imhdu.append(scihdu.copy())
+    d2imhdu.writeto(outname)
+    d2imhdu.close()
+
+    return outname
+
+
+def removeFileSafely(filename,clobber=True):
+    """ Delete the file specified, but only if it exists and clobber is True.
+    """
+    if filename is not None and filename.strip() != '':
+        if os.path.exists(filename) and clobber: os.remove(filename)