diff options
Diffstat (limited to 'distortion/utils.py')
| -rw-r--r-- | distortion/utils.py | 31 |
1 files changed, 29 insertions, 2 deletions
diff --git a/distortion/utils.py b/distortion/utils.py index 06bf5f8..bc25daf 100644 --- a/distortion/utils.py +++ b/distortion/utils.py @@ -1,9 +1,11 @@ from __future__ import division # confidence high +import os import numpy as np import pywcs import pyfits from stwcs import wcsutil from numpy import sqrt, arctan2 +from pytools import fileutil def output_wcs(list_of_wcsobj, ref_wcs=None, outwcs=None, undistort=True): fra_dec = np.vstack([w.calcFootprint() for w in list_of_wcsobj]) @@ -52,6 +54,18 @@ def undistortWCS(wcsobj): import coeff_converter cx, cy = coeff_converter.sip2idc(wcsobj) + # cx, cy can be None because either there is no model available + # or updatewcs was not run. + if cx == None or cy == None: + if foundIDCTAB(wcsobj.idctab): + m = """IDCTAB is present but distortion model is missing. + Run updatewcs() to update the headers or + pass 'undistort=False' keyword to output_wcs().\n + """ + raise RuntimeError, m + else: + print 'Distortion model is not available, using input reference image for output WCS.\n' + return wcsobj.copy() crpix1 = wcsobj.wcs.crpix[0] crpix2 = wcsobj.wcs.crpix[1] xy = np.array([(crpix1,crpix2),(crpix1+1.,crpix2),(crpix1,crpix2+1.)],dtype=np.double) @@ -75,8 +89,8 @@ def undistortWCS(wcsobj): if ( _det == 0.0): print 'Singular matrix in updateWCS, aborting ...' return - #lin_wcsobj = wcsutil.HSTWCS(instrument=wcsobj.instrument) - lin_wcsobj = pywcs.WCS() #instrument=wcsobj.instrument) + + lin_wcsobj = pywcs.WCS() cd_inv = np.linalg.inv(cd_mat) lin_wcsobj.wcs.cd = np.dot(wcsobj.wcs.cd, cd_inv) @@ -120,4 +134,17 @@ def apply_idc(pixpos, cx, cy, pixref, pscale= None, order=None): return c +def foundIDCTAB(idctab): + idctab_found = True + try: + idctab = fileutil.osfn(idctab) + if idctab == 'N/A' or idctab == "": + idctab_found = False + if os.path.exists(idctab): + idctab_found = True + else: + idctab_found = False + except KeyError: + idctab_found = False + return idctab_found |