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coordsys.referencepixel - Function

1.1.3 Recover the reference pixel


Description

Each axis associated with the Coordinate System has a reference value, reference pixel and an increment (per pixel). These are used in the mapping from pixel to world coordinate.

This function returns the reference pixel (in pixel axis order). You can recover the reference pixel either for all coordinates (leave type unset) or for a specific coordinate type (mimumum match of the allowed types will do). If you ask for a non-existent coordinate an exception is generated.

You can set the reference pixel with function setreferencepixel.

Arguments





Inputs

type

Coordinate type: ”direction”, ”stokes”, ”spectral”, ”linear”, ”tabular”. Leave empty for all.

allowed:

string

Default:

Returns
record

Example

 
 
"""  
#  
print "\t----\t referencepixel Ex 1 \t----"  
csys = cs.newcoordsys(spectral=T, linear=2)  
csys.setreferencepixel([1.0, 2.0, 3.0])  
print csys.referencepixel()  
#{’ar_type’: ’absolute’, ’pw_type’: ’pixel’, ’numeric’: array([ 1.,  2.,  3.])}  
print csys.referencepixel(’lin’)  
#{’ar_type’: ’absolute’, ’pw_type’: ’pixel’, ’numeric’: array([ 2.,  3.])}  
#  
"""  
 

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