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imagepol.sigmadepolratio - Function
1.1.4 Error in linear depolarization ratio
Description
This function returns the error in the linear depolarization ratio computed
from two frequencies; this is the ratio of the fractional linear polarization at the
two frequencies. Generally this is done when you have generated two images,
each at a different frequency (continuum work). Thus if the fractional linear
polarzation images are m1 and m2 then the depolarization ratio is m1∕m2.
This function operates with two images; the first is attached to the Imagepol tool. The second is supplied via the argument infile, which is a String holding the name of the image file.
In generating the depolarization ratio, and hence its error, you may optionally debias the linearly polarized intensity. This 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.
You can get the depolarization ratio image with function depolratio.
Arguments
Inputs |
| ||
infile |
| Other image. Required input.
| |
| allowed: | string |
|
| Default: |
| |
debias |
| Debias the linearly polarized intensity ?
| |
| allowed: | bool | |
| Default: | false |
|
clip |
| Clip level for auto-sigma determination
| |
| allowed: | double |
|
| Default: | 10.0 |
|
sigma |
| Standard deviation of thermal noise. Default is auto
determined.
| |
| allowed: | double |
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| Default: | -1 |
|
outfile |
| Output image file name. Default is unset.
| |
| allowed: | string |
|
| Default: |
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image
Example
"""
#
#print "\t----\t sigmadepolratio Ex 1 \t----"
#po.open(’stokes.4800’)
#dpr = po.depolratio(’stokes.8300’)
#edpr = po.sigmadepolratio(’stokes.8300’);
#dpr.done()
#edpr.done()
#
"""
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This code is available under the terms of the GNU General Public Lincense
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