Content-type: text/html Manpage of uvdiff

uvdiff

Section: User Commands (1)
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NAME

uvdiff - Difference two visibility datasets.  

PERSON RESPONSIBLE

rjs  

CATEGORIES

uv analysis  

DESCRIPTION

Given two Miriad visibility datasets, UVDIFF matches and optionally subtracts one from the other. In doing this, UVDIFF assumes that the two datasets sample the same source using the same array configuration and observing frequency setup (no checks are made to verify these). UVDIFF matches visibility records based on baseline number, polarisation type and hour angle. If the hour angles in the two datasets do not match to better than 1 second, UVDIFF linearly interpolates between two integrations of one dataset to the appropriate hour angle of the other.

NOTE: UVDIFF does not apply calibration corrections to either of the input datasets. The datasets should be in time order.  

PARAMETERS

vis
The two datasets to difference. No default. When differencing, the output is the first minus the second. The first visibility dataset is used as the template for the output. It is the second dataset that is interpolated when needed.
select
Standard visibility selection keyword. See the help on "select" for more information. Note that this selection is applied ONLY to the first visibility dataset. The default is to select everything.
out
The output dataset. No default.
mode
This determines what data is written. Possible values are:
  difference Write the difference of the two inputs (the first
             minus the second).  This is the default.
  two        Write the data from the second input, interpolated
             to the first.
  one        Write the first dataset.
With the exception of the visibility data itself, all three possibilities will produce identical datasets. This includes identical flagging information. Any of these modes can be prefixed with a minus sign. In this case the output visibilities are negated.
tol
Interpolation tolerance, in minutes. This gives the maximum gap between two integrations to interpolate across. The default is 2 minutes.


 

Index

NAME
PERSON RESPONSIBLE
CATEGORIES
DESCRIPTION
PARAMETERS

This document was created by man2html, using the manual pages.
Time: 18:35:38 GMT, July 05, 2011