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imagepol.sigmatotpolint - Function

1.1.4 Error in total polarized intensity


Description

This function returns the error (standard deviation) of the total polarized intensity; ∘--------------
 (Q2 + U2 + V2). This result comes from standard propagation of statistical errors. The result is a float as the error is not 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

Returns
double

Example

 
 
"""  
#  
print "\t----\t sigmastotpolint Ex 1 \t----"  
po.open(’stokes.image’)  
sigtpi = po.sigmatotpolint()  
print "sigtpi=", sigtpi  
#  
"""  
 

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