NRAO Home > CASA > CASA Toolkit Reference Manual
coordsys.setreferencelocation - Function

1.1.3 Set reference pixel and value


Description

This function sets the reference pixel and reference value to the specified values. The world coordinate can be specified in any of the formats that the output world coordinate is returned in by the toworld function.

You can specify a mask (argument mask) indicating which pixel axes are set (T) and which are left unchanged (F). This function will refuse to change the reference location of a Stokes axis (gets you into trouble otherwise).

This function can be rather useful when regridding images. It allows you to keep easily a particular feature centered in the regridded image.

Arguments





Inputs

pixel

New reference pixel. Defaults to old reference pixel.

allowed:

intArray

Default:

-1

world

New reference value. Defaults to old reference value.

allowed:

any

Default:

variant -1

mask

Indicates which axes to center. Defaults to all.

allowed:

boolArray

Default:

false

Returns
bool

Example

 
 
"""  
#  
print "\t----\t setreferencelocation Ex 1 \t----"  
csys = cs.newcoordsys(linear=2)  
print csys.referencepixel()  
#[0.0, 0.0]  
print csys.referencevalue()  
#{’numeric’: array([ 0.,  0.])}  
w = csys.toworld([19,19], format=’n’)  
shp = [128,128]  
p = [64, 64]  
csys.setreferencelocation (pixel=p, world=w)  
print csys.referencepixel()  
#[64.0, 64.0]  
print csys.referencevalue()  
#{’numeric’: array([ 19.,  19.])}  
#  
"""  
 

__________________________________________________________________


More information about CASA may be found at the CASA web page

Copyright 2016 Associated Universities Inc., Washington, D.C.

This code is available under the terms of the GNU General Public Lincense


Home | Contact Us | Directories | Site Map | Help | Privacy Policy | Search