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imagepol.sigmafraclinpol - Function

1.1.4 Error in fractional linear polarization


Description

This function returns the error (standard deviation) of the fractional linear polarization. This result comes from standard propagation of errors. The result is an on-the-fly Image tool as the error is signal-to-noise ratio dependent.

This function requires the standard deviation of the thermal noise. You can either supply it if you know it, or it will be worked out for you with outliers from the mean clipped at the specified level.

Arguments





Inputs

clip

Clip level for auto-sigma determination

allowed:

double

Default:

10.0

sigma

Standard deviation of thermal noise. Default is auto determined.

allowed:

double

Default:

-1

outfile

Output image file name. Default is unset.

allowed:

string

Default:

Returns
image

Example

 
 
 
"""  
#  
print "\t----\t sigmafraclinpol Ex 1 \t----"  
po.open(’stokes.image’)  
sigflp = po.sigmafraclinpol()  
sigflp.statistics()  
sigflp.done()           # free up resources  
#  
"""  
 

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