AIPS HELP file for UVFRE in 31DEC24
As of Wed Oct 9 3:23:02 2024
UVFRE: regrids one data set on the frequency setup of a second
INPUTS
INNAME Input UV file name (name)
INCLASS Input UV file name (class)
INSEQ 0.0 9999.0 Input UV file name (seq. #)
INDISK 0.0 9.0 Input UV file disk unit #
IN2NAME Master UV file name (name)
IN2CLASS Master UV file name (class)
IN2SEQ 0.0 9999.0 Master UV file name (seq. #)
IN2DISK 0.0 9.0 Master UV file disk unit #
SOURCES Source name
QUAL -10.0 Calibrator qualifier -1=>all
CALCODE Calibrator code ' '=>all
TIMERANG Time range to use
SELBAND Bandwidth to select (kHz)
SELFREQ Frequency to select (MHz)
FREQID Freq. ID to select.
SUBARRAY 0.0 1000.0 Sub-array, 0=>all
DOCALIB -1.0 101.0 > 0 calibrate data & weights
> 99 do NOT calibrate weights
GAINUSE CL (or SN) table to apply
DOPOL -1.0 10.0 If >0.5 correct polarization.
PDVER PD table to apply (DOPOL>0)
BLVER BL table to apply.
FLAGVER Flag table version
DOBAND -1.0 10.0 If >0.5 apply bandpass cal.
Method used depends on value
of DOBAND (see HELP file).
BPVER Bandpass table version
SMOOTH Smoothing function. See
HELP SMOOTH for details.
DOACOR Include autocorrelations?
INTPARM Frequency gridding function
(1) 0 -> simple, 1 Hanning
2 Gaussian, 3, Boxcar,
4 Sinc, 5 Exponential
(2) width, (3) support
OUTNAME Output UV file name (name)
OUTCLASS Output UV file name (class)
OUTSEQ -1.0 9999.0 Output UV file name (seq. #)
OUTDISK 0.0 9.0 Output UV file disk unit #.
BADDISK Disks to avoid for scratch
HELP SECTION
UVFRE
Task: This task will regrid the visibility data of one data set to
the frequency structure of another. This regridding may be
done with a convolution in frequency or a simple pillbox-like
operation. Overlapped channels will be averaged and missing
channels will be flagged. All calibration will be removed from
the data set, so it is very important to apply all of it to the
data as they are read into this task --- or before of course.
Adverbs:
INNAME.....Input UV file name (name). Standard defaults.
INCLASS....Input UV file name (class). Standard defaults.
INSEQ......Input UV file name (seq. #). 0 => highest.
INDISK.....Disk drive # of input UV file. 0 => any.
IN2NAME....Master UV file name (name). Standard defaults.
IN2CLASS...Master UV file name (class). Standard defaults.
IN2SEQ.....Master UV file name (seq. #). 0 => highest.
IN2DISK....Disk drive # of master UV file. 0 => any.
SOURCES....Source to be copied. ' '=> all; if any starts with a
'-' then all except ANY source named.
QUAL.......Qualifier of source to be copied. -1 => all.
CALCODE....Calibrator code of sources to copy. ' '=> all.
TIMERANG...Time range of the data to be copied. In order: Start day,
hour, min. sec, end day, hour, min. sec. Days relative to
ref. date.
SELBAND....Bandwidth of data to be selected. If more than one IF is
present SELBAND is the width of the first IF required.
Units = kHz. For data which contain multiple
bandwidths/frequencies the task will insist that some form
of selection be made by frequency or bandwidth.
SELFREQ....Frequency of data to be selected. If more than one IF is
present SELFREQ is the frequency of the first IF required.
Units = MHz.
FREQID.....Frequency identifier to select (you may determine which is
applicable from the OPTYPE='SCAN' listing produced by
LISTR). If either SELBAND or SELFREQ are set, their values
override that of FREQID. However, setting SELBAND and
SELFREQ may result in an ambiguity. In that case, the task
will request that you use FREQID.
SUBARRAY...Sub-array number to copy. 0=>all.
DOCALIB....If true (>0), calibrate the data using information in the
specified Cal (CL) table for multi-source or SN table for
single-source data. Also calibrate the weights unless
DOCALIB > 99 (use this for old non-physical weights).
GAINUSE....version number of the CL table to apply to multi-source
files or the SN table for single source files.
0 => highest.
DOPOL......If > 0 then correct data for instrumental polarization as
represented in the AN or PD table. This correction is
only useful if PCAL has been run or feed polarization
parameters have been otherwise obtained. See HELP DOPOL
for available correction modes: 1 is normal, 2 and 3 are
for VLBI. 1-3 use a PD table if available; 6, 7, 8 are
the same but use the AN (continuum solution) even if a PD
table is present.
PDVER......PD table to apply if PCAL was run with SPECTRAL true and
0 < DOPOL < 6. <= 0 => highest.
BLVER......Version number of the baseline based calibration (BL) table
to apply. <0 => apply no BL table, 0 => highest.
FLAGVER....specifies the version of the flagging table to be applied.
0 => highest numbered table.
<0 => no flagging to be applied.
DOBAND.....If true (>0) then correct the data for the shape of the
antenna bandpasses using the BP table specified by BPVER.
The correction has five modes:
(a) if DOBAND=1 all entries for an antenna in the table
are averaged together before correcting the data.
(b) if DOBAND=2 the entry nearest in time (including
solution weights) is used to correct the data.
(c) if DOBAND=3 the table entries are interpolated in
time (using solution weights) and the data are then
corrected.
(d) if DOBAND=4 the entry nearest in time (ignoring
solution weights) is used to correct the data.
(e) if DOBAND=5 the table entries are interpolated in
time (ignoring solution weights) and the data are then
corrected.
IMAGR uses DOBAND as the nearest integer; 0.1 is therefore
"false".
BPVER......Specifies the version of the BP table to be applied
0 => highest numbered table.
<0 => no bandpass correction to be applied.
SMOOTH.....Specifies the type of spectral smoothing to be applied to
a uv database . The default is not to apply any smoothing.
The elements of SMOOTH are as follows:
SMOOTH(1) = type of smoothing to apply: 0 => no smoothing
To smooth before applying bandpass calibration
1 => Hanning, 2 => Gaussian, 3 => Boxcar, 4 => Sinc
To smooth after applying bandpass calibration
5 => Hanning, 6 => Gaussian, 7 => Boxcar, 8 => Sinc
SMOOTH(2) = the "diameter" of the function, i.e. width
between first nulls of Hanning triangle and sinc
function, FWHM of Gaussian, width of Boxcar. Defaults
(if < 0.1) are 4, 2, 2 and 3 channels for SMOOTH(1) =
1 - 4 and 5 - 8, resp.
SMOOTH(3) = the diameter over which the convolving
function has value - in channels. Defaults: 1,3,1,4
times SMOOTH(2) used when input SMOOTH(3) < net
SMOOTH(2).
DOACOR.....> 0 => include autocorrelations as well as cross
correlation data.
INTPARM....The input visibility spectra are interpolated to the
output under control of INTPARM:
INTPARM(1) = type of interpolation (weighted smoothing)
to use
0 => Weighted substitution (INTPARM(2 and 3)
ignored)
1 => Hanning
2 => Gaussian
3 => Boxcar
4 => Sinc (i.e. sin(x)/x)
5 => Exponential
INTPARM(2) = the "diameter" of the function, i.e. width
between first nulls of Hanning triangle and sinc
function, FWHM of Gaussian, Exponential, width of
Boxcar. Defaults (if < 0.1) are 4, 2, 2, 3, 1.99 INPUT
channels for INTPARM(1) = 1 - 5.
INTPARM(3) = the diameter over which the convolving
function has value - in INPUT channels. Defaults: 1,
3, 1, 4, 3 times INTPARM(2) used when input INTPARM(3)
< INTPARM(2) (after application of defaults).
OUTNAME....Output UV file name (name). Standard defaults.
OUTCLASS...Output UV file name (class). Standard defaults.
OUTSEQ.....Output UV file name (seq. #). 0 => highest unique
OUTDISK....Disk drive # of output UV file. 0 => highest with space
for the file.
BADDISK....The disk numbers to avoid for scratch files (sorting
tables mostly).
EXPLAIN SECTION