diff options
Diffstat (limited to 'distortion/utils.py')
| -rw-r--r-- | distortion/utils.py | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/distortion/utils.py b/distortion/utils.py index a6b4fa5..06bf5f8 100644 --- a/distortion/utils.py +++ b/distortion/utils.py @@ -1,12 +1,11 @@ -from __future__ import division # confidence high - +from __future__ import division # confidence high import numpy as np import pywcs import pyfits from stwcs import wcsutil from numpy import sqrt, arctan2 -def output_wcs(list_of_wcsobj, ref_wcs=None, outwcs=None): +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]) delta_fdec = (fra_dec[:,1].max()-fra_dec[:,1].min()) @@ -19,8 +18,10 @@ def output_wcs(list_of_wcsobj, ref_wcs=None, outwcs=None): if outwcs is None: if ref_wcs == None: ref_wcs = list_of_wcsobj[0] - - outwcs = undistortWCS(ref_wcs) + if undistort: + outwcs = undistortWCS(ref_wcs) + else: + outwcs = ref_wcs.copy() outwcs.wcs.crval = crval outwcs.pscale = sqrt(outwcs.wcs.cd[0,0]**2 + outwcs.wcs.cd[1,0]**2)*3600. outwcs.orientat = arctan2(outwcs.wcs.cd[0,1],outwcs.wcs.cd[1,1]) * 180./np.pi @@ -42,6 +43,11 @@ def output_wcs(list_of_wcsobj, ref_wcs=None, outwcs=None): return outwcs def undistortWCS(wcsobj): + """ + Creates an undistorted linear WCS by applying the IDCTAB distortion model + to a 3-point square. The new ORIENTAT angle is calculated as well as the + plate scale in the undistorted frame. + """ assert isinstance(wcsobj, pywcs.WCS) import coeff_converter |