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getfs.pro

Last modification date:
Thu Jun 2 23:56:08 2005

Routine Summary  2 routines

procedure getfs, scan, [ifnum=integer], [intnum=integer], [plnum=integer], [fdnum=integer], [tau=float], [ap_eff=float], [units=string], [nofold=flag], [noweight=flag]

This procedure retrieves and calibrates a frequency switched scan.

procedure dofsint, sigwcal, sig, refwcal, ref, tau, ap_eff, units, nofold[, ret_tau], result1=variable, [result2=variable]

private

This procedure calibrates a single integration from a FS scan.

Routine Details

getfs

procedure getfs, scan, [ifnum=integer], [intnum=integer], [plnum=integer], [fdnum=integer], [tau=float], [ap_eff=float], [units=string], [nofold=flag], [noweight=flag]

This procedure retrieves and calibrates a frequency switched scan. Frequency switched data obtained with other procedure names will be rejected by this procedure. This code should be used as a template for the user who may wish to develop more sophisticated calibration schemes or reduce frequency switched data from other types of procedures. This routine produces a spectrum calibrated in Ta (K) (other recognized units are 'Ta*' and 'Jy').

The only required parameter is the scan number. Arguments to identify the IF number, polarization number, and feed number are optional. A zenith opacity can be entered. The program calculates Tsys based on the Tcal values, and cal_on/cal_off phases.

All averaging is done using dcaccum and accumave. This means that integrations are weighted using the default weight given in dcaccum. To turn off this weighting so that all integrations have equal weight in the average, use the /noweight flag.

There must be 4 switching states and the SWITCH_STATE value must be 'FSWITCH'.

Examples
    getfs,76
    accum
    getfs,77
    accum
    ave
    show
 

a nofold example, show each half and then fold

    getfs,76,/nofold
    oshow,1
    fold
 
Uses
dcfold
Version
$Id: getfs.pro,v 1.21 2005/05/30 04:03:43 bgarwood Exp $

Parameters
scan
in, required
integer
scan number

Keywords
ifnum
in, optional
integer
IF number
intnum
in, optional
integer
integration number
plnum
in, optional
integer
polarization index (0 or 1)
fdnum
in, optional
integer
feed number (default 0)
tau
in, optional
float
tau at zenith
ap_eff
in, optional
float
aperture efficiency
units
in, optional
string
takes the value 'Jy', 'Ta', or 'Ta*'
nofold
in, optional
flag
if set, does no folding. When this is set, data container 0 contains the results of (sig-ref)/ref while data container 1 contains the results of (ref-sig)/sig, calibrated independently and averaged over all integrations. Only data container 0 will be shown.
noweight
in, optional
flag
if set, the default weighting is turned off and all integrations are averaged with the same weight (1.0).

dofsint private

procedure dofsint, sigwcal, sig, refwcal, ref, tau, ap_eff, units, nofold[, ret_tau], result1=variable, [result2=variable]

This procedure calibrates a single integration from a FS scan. This is currently an internal function used only by getfs.

Version
$Id: getfs.pro,v 1.21 2005/05/30 04:03:43 bgarwood Exp $

Parameters
sigwcal
in, required
spectrum
An uncalibrated spectrum from the signal phase with the cal on.
sig
in, required
spectrum
An uncalibrated spectrum from the signal phase with the cal off. An uncalibrated spectrum from the reference phase with the cal off.
refwcal
in, required
spectrum
An uncalibrated spectrum from the reference phase with the cal on.
ref
.
tau
in, required
float
tau at zenith
ap_eff
in, required
float
aperture efficiency
units
in, required
string
units for calibration ('Ta', 'Ta*', or 'Jy')
nofold
in, required
string
units for calibration ('Ta', 'Ta*', or 'Jy')
ret_tau
out, optional
variable
returned tau; internal use

Keywords
result1
out, required
variable
The primary result. If nofold is not set (the default case) then this contains the calibrated, folded result. If nofold is set, then this contains the calibrated result for 1/2 of the switching phase (sig-ref)/ref.
result2
out, optional
variable
This value is only set when nofold is set. In that case, this contains the calibrated result for the other 1/2 of the switching phase (ref-sig)/sig.


Produced by IDLdoc 1.6 on Thu Jun 2 23:56:14 2005