imregrid.py

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#
# This file was generated using xslt from its XML file
#
# Copyright 2009, Associated Universities Inc., Washington DC
#
import sys
import os
from  casac import *
import string
from taskinit import casalog
#from taskmanager import tm
import task_imregrid
def imregrid(imagename='', template='get', output='', asvelocity=False, axes=[-1], shape=[-1]):

        """regrid an image onto a template image

imregrid: regrid an image to a new coordinate system.

Keyword arguments:
imagename   Name of the image that needs to be regridded
            default: none; example: imagename='orion.image'
template    Dictionary, reference code, or imagename defining the new
            shape and coordinate system, or 'get' to return the template
            dictionary for imagename.  Recognized reference codes are:
            'J2000', 'B1950', 'B1950_VLA', 'GALACTIC', 'HADEC', 'AZEL',
            'AZELSW', 'AZELNE', 'ECLIPTIC', 'MECLIPTIC', 'TECLIPTIC',
            and 'SUPERGAL'.
            default: 'get'; example: template='orion_j2000.im'
shape       Shape of the output image. Only used if template is an image.
            If not specified (-1), the output image shape is set equal to
            the input image shape.
output      Name for the regridded image
            default: imagename + '.regridded'; example: imagename='orion_shifted.im'
asvelocity  Regrid spectral axis with respect to velocity, not frequency?
            default: False
axes        The pixel axes to regrid. -1 => all.
async       Run task in a separate process (return CASA prompt)
            default: False; example: async=True
                
The new coordinate system is defined by the template parameter,
which can be:
    * a recognized reference code string (see below),
    * a {'csys': csys_record, 'shap': shape} dictionary,
    * 'get', which does not regrid but returns the template dictionary
      for imagename, suitable for modification and reuse, or
    * the name of an image to get the coordinate system and shape
      from.  The input and template images must have the same
      coordinate structure.
      
If one of the axes to be regridded is a spectral axis and asvelocity=T,
the axis will be regridded to match the velocity, not the frequency,
description of the template coordinate system. Thus the output pixel
values will correspond only to the velocity, not the frequency, of the
output axis.

If an image has per-plane beams and one attempts to regrid the spectral axis,
an exception is thrown.



        """
        if type(axes)==int: axes=[axes]
        if type(shape)==int: shape=[shape]

#
#    The following is work around to avoid a bug with current python translation
#
        mytmp = {}

        mytmp['imagename'] = imagename
        mytmp['template'] = template
        mytmp['output'] = output
        mytmp['asvelocity'] = asvelocity
        mytmp['axes'] = axes
        mytmp['shape'] = shape
        pathname='file:///'+os.environ.get('CASAPATH').split()[0]+'/share/xml/'
        trec = casac.utils().torecord(pathname+'imregrid.xml')

        casalog.origin('imregrid')
        if trec.has_key('imregrid') and casac.utils().verify(mytmp, trec['imregrid']) :
            result = task_imregrid.imregrid(imagename, template, output, asvelocity, axes, shape)

        else :
          result = False
        return result