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image.newimagefromfits - Function

1.1.1 Construct a CASA image by conversion from a FITS image file


Description

This function is used to convert a FITS disk image file (Float, Double, Short, Long are supported) to an CASA image file. If outfile is given, the image is written to the specified disk file. If outfile is unset, the on-the-fly Image tool returned by this function is associated with a temporary image. This temporary image may be in memory or on disk, depending on its size. When you destroy the on-the-fly Image tool (with the done function) this temporary image is deleted.

This function reads from the FITS primary array (when the image is at the beginning of the FITS file; whichhdu=0), or an image extension (when the image is elsewhere in the FITS file, whichhdu > 0).

By default, any blanked pixels will be converted to a mask value which is false, and a pixel value that is NaN. If you set zeroblanks=T then the pixel value will be zero rather than NaN. The mask will still be set to false. See the function replacemaskedpixels if you need to replace masked pixel values after you have created the image.

Arguments





Inputs

outfile

Output image file name. Default is unset.

allowed:

string

Default:

infile

Input FITS disk file name. Required.

allowed:

string

Default:

whichrep

If this FITS file contains multiple coordinate representations, which one should we read

allowed:

int

Default:

0

whichhdu

If this FITS file contains multiple images, which one should we read (0-based).

allowed:

int

Default:

0

zeroblanks

If there are blanked pixels, set them to zero instead of NaN

allowed:

bool

Default:

false

overwrite

Overwrite (unprompted) pre-existing output file?

allowed:

bool

Default:

false

Returns
image

Example

 
 
"""  
#  
print "\t----\t newimagefromfits Ex 1 \t----"  
# Assume we can find test fits file using  
# CASAPATH environment variable  
pathname=os.environ.get("CASAPATH")  
pathname=pathname.split()[0]  
datapath=pathname+’/data/demo/Images/imagetestimage.fits’  
im1=ia.newimagefromfits(’./myimage’, datapath, overwrite=true)  
print im1.summary()  
print im1.miscinfo()  
print ’fields=’, im1.miscinfo().keys()  
im1.done()  
#  
"""  
 
 
The FITS image is converted to a \casa\ \imagefile\ and access is  
provided via the \imagetool\ called {\stf im1}.  Any FITS header  
keywords which were not recognized or used are put in the  
miscellaneous information bucket accessible with the miscinfo function.  In  
the example we list the names of the fields in this record.  
 

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