./contrib
sdextract.pro

Last modification date:

Wed Sep 28 13:27:15 2016

sdextract

procedure sdextract, sdfin, sdfout, [startat=integer], [endat=integer], [boxwidth=integer], [/clobber], _EXTRA=_EXTRA

A function to extract a range of channels from all of the spectra in an input SDFITS file and write the resulting spectra out to a second SDFITS file. This also optionally does a boxcar smooth with decimation. The boxcar smoothing happens after the region of interest has been extracted.

Any valid data selection arguments can also be given. See select for more details.

Uses dcextract to extract the sub-spectra and dcboxcar to do the boxcar smoothing. See those reference pages for additional details of these two steps.

The input file must exist and be readable. The output file must not exist or clobber must be set to remove an existing file. If the output file already exists and is a directory it will not be removed, even if clobber is set.

Error checking on the startat and endat values happens in dcextract. If that routine returns -1 at any time, this routine exits and any already processed data is written to sdfout.

Contributed By: Bob Garwood, NRAO-CV

Uses

dcboxcar dcextract

Parameters
sdfin in, required string	The intput FITS file. This must already exist.
sdfout in, required string	The output FITS file. If this file exists then clobber must be set so that the file is deleted before being written to. This routine always writes to an empty output file. The file name must end in '.fits'

Keywords
startat in, optional integer (def. 0)	The first channel to include in the extracted region (counting from 0).
endat in, optional integer	The last channel to include in the extracted region (counting from 0). If not supplied, the last channel is used. endad must be greater than or equal to startat.
boxwidth in, optional integer	The width of the boxcar, in channels, to apply to the data. The data is further reduced when this value is greater than 1 by taking every width channels starting at channel 0. Boxcar smoothing happens after any region extraction specified by startat and endat have been done.
clobber in, optional boolean	When set, if sdfout exists, it will first be deleted (including any associated index file).
_EXTRA	.