AIPS HELP file for UVFND in 31DEC24
As of Mon Apr 29 5:37:26 2024
UVFND: Task to print selected source data from a UV disk file
INPUTS
INNAME UV data (name).
INCLASS UV data (class).
INSEQ 0.0 9999.0 UV data (seq. #). 0 => high
INDISK 0.0 9.0 Disk unit #. 0 => any
BCHAN 0.0 Start channel to test
ECHAN 0.0 Last channel to test
NCHAV 0.0 Number channels to average
CHANNEL 0.0 9999.0 Frequency channel to print
BIF 0.0 32767.0 IF number to test.
NITER 0.0 32767.0 Max # lines printed.
0 => 10 pages
UVRANGE 0.0 UV range in kilolambda
STOKES Stokes parameters: ' ' => 'I'
'CORR' for correlators
SOURCES Source list
QUAL -10.0 Calibrator qualifier -1=>all
CALCODE Calibrator code ' '=>all
TIMERANG Time range
SELBAND Bandwidth to select (kHz)
SELFREQ Frequency to select (MHz)
FREQID Freq. ID to select.
None selected => 1.
ANTENNAS Antennas to list
BASELINE Baselines with ANTENNAS
SUBARRAY 0.0 1000.0 Sub-array, 0=>all
DOCALIB -1.0 101.0 > 0 calibrate data & weights
> 99 do NOT calibrate weights
GAINUSE CAL (CL or SN) table to apply
DOPOL -1.0 10.0 If >0 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 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.
OPCODE 'CLIP' print excess fluxes
'FRNG' print all in annulus
'UVBX' print points in uv box
'VCLP' print excess (RR-LL)/2
'WTUV' check weights & excess
fluxes
APARM CLIP:(1) peak ok flux IPOL
(2) peak ok pol. flux
(3) min. ok flux IPOL
(4) min. ok pol flux
(5) peak ok phase IPOL
(6) peak ok pol. phase
(7) min. ok phase IPOL
(8) min. ok pol phase
FRNG:(1) fringe spacing arsec
(2) range fringe spacing
(3) baseline pos. angle
(4) range of pos. angle
UVBX:(1) U in kilolambda
(2) range of U
(3) V in kilolambda
(4) range of V
(5) >0 => Hermitian too
VCLP:(1) peak ok VPOL flux
DOSCALE -1.0 2.0 > 0 => Scale vis by source
flux; = 2 use spectral index
WTUV 0.0 Maximum "reasonable" weight
used only with 'WTUV'
0 => infinity
DOCRT -3.0 132.0 > 0 -> use CRT, else printer
> 72 => CRT width in chars
OUTPRINT
Printer disk file to save
BADDISK Disks to avoid for scratch
HELP SECTION
UVFND
Type: Task
Use: List visibility points from a catalogued UV data file meeting
criteria set by OPCODE and APARM. One may print on the line
printer (or the user's terminal) those points having flux greater
than specified cutoffs (separate parallel- hand and cross
polarization limits). One may print those samples having an
apparent circular polarization greater than some specified
cutoff. Or one may print all samples lying within a specified
portion of the UV plane. On all OPCODEs, the data are checked
for having reasonable times, antenna numbers, and (optionally)
weights. Any which don't are printed.
UVFND will also work on single disk data giving an appropriate
listing of the data. OPCODE='UVBX' allows a window in RA and dec
(in degrees) to be specified.
Adverbs:
INNAME.....UV file name (name). Standard defaults.
INCLASS....UV file name (class). Standard defaults.
INSEQ......UV file name (seq. #). 0 => highest.
INDISK.....Disk unit #. 0 => any.
BCHAN......Initial channel examined: 0 -> 1
ECHAN......Last channel examined: < BCHAN -> max
NCHAV......The channels in BCHAN-ECHAN are averaged combining NCHAV
channels in each average (0 -> 1)
CHANNEL....First frequency channel to print: 0 -> (BCHAN+ECHAN+1)/2
BIF........IF number to test. 0 => 1.
NITER......Do not list more than NITER points. 0 => no more than 10
pages.
UVRANGE....Limit print to baselines >= UVRANGE(1) and <= UVRANGE(2) in
kilo wavelengths. 0 => all. Ignored for 'UVBX'.
SOURCES....List of sources to be listed. ' '=> all; if any starts
with a '-' then all except ANY source named.
QUAL.......Qualifier of source to be examined. -1 => all.
CALCODE....Calibrator code of sources to be examined. ' '=> all.
TIMERANG...Time range of the data to be listed. In order:
Start day, hour, min. sec,
end day, hour, min. sec. Days relative to ref.
date.
STOKES.....Limit data tested and printed to the specified STOKES
type(s). Can be 'I','IQU','IV','IQUV','RR','LL','RL'.
blank => 'I'. A special value ('CORR') is allowed to imply
all correlators with no modification.
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, 0=> all
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, 0=> all
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
overide that of FREQID. However, setting SELBAND and
SELFREQ may result in an ambiguity. In that case the task
will request that you use FREQID. If neither SELBAND,
SELFREQ nor FREQID are specified then the first FQ id in
the FQ table (usually 1) will be used.
ANTENNAS...A list of the antennas to examine. If any number is
negative then all antenna numbers in ANTENNAS are NOT
desired and all others are. All 0 => examine all.
Note that antenna numbers that do not appear in the
relevant antenna file(s) or which appear with a name
containing the string 'OUT' are not displayed.
BASELINE...Baselines are specified using BASELINE. Eg. baselines
1-6,1-8, 2-6 and 2-8 use ANTENNAS=1,2; BASELINE=6,8.
SUBARRAY...Sub-array number to use. 0=>all; if DOCAL > 0 then multiple
subarrays (SUBARRAY = 0) are not allowed.
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 Cal. table to apply to the data if
DOCALIB=1. Refers to a CL table for multisource data of an
SN table for single source. 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 appply. <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.
BPVER......Specifies the version of the BP table to be applied.
<0 => no bandpass correction done.
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).
OPCODE.....If 'CLIP' program applies excess flux test
If 'FRNG' program lists points in area of UV plane
If 'UVBX' program lists points in area of UV plane
If 'VCLP' program applies excess V pol. test
If 'WTUV' program applies reasonable weight test and
excess flux test.
If anything else, just do integrity tests.
APARM......For CLIP abd WTUV, APARM(1) is max normal flux (Jy) for
total intensity and APARM(2) for polarization. APARM(3)
is the min normal flux (Jy) for total intensity and
APARM(4) for polarization. For interferometers, <= 0 =>
no test; there are NO defaults for single-dish data.
Phase may also be tested: APARM(5) is the max normal
phase (degrees) for total intensity (0 -> 180), APARM(6)
is the max for polarization. APARM(7) is the minimum
normal phase for total intensity (0 -> -180) and APARM(8)
for polarization.
For FRNG, APARM(1) is the separation of the fringes in your
map in arc seconds. APARM(2) is the range of this
separation to be included in listing. APARM(3) is the
baseline position angle in deg. and APARM(4) is the range
of pos. angle.
For UVBX, APARM(1) and APARM(3) give the central values of
U and V (in kilolambda) of a rectangular area in the UV
plane. APARM(2) and APARM(4) give the half-widths of the
area for U and V (in kilo-lambda). APARM(5) is a logical
which says, if >0, to display also data at the Hermitian
box. For single dish data and OPCODE='UVBX' the specified
region is in RA and Dec (degrees) if unprojected data or in
projected coordinates for projected data.
For VCLP, APARM(1) is the max allowed circular polarization
flux ( (RR - LL) / 2 in Jy).
DOSCALE....> 0 => use source fluxes from source table; = 2 fit and
use spectral index also. Fluxes are then scaled by these
expected fluxes, so the values in APARM should be for
normalized visibilities.
WTUV.......Maximum "reasonable" weight --- data with weights greater
will be printed. 0 => don't check. This is done if
OPCODE is WTUV, otherwise it is ignored.
DOCRT......False (<= 0) use the line printer if OUTPRINT = ' '
else write named OUTPRINT file only.
When OUTPRINT is not blank, DOCRT=-2 suppresses the
page-feed character on page headers and DOCRT=-3
suppresses page headers and most other header
information.
True (> 0) use the terminal interactively. The task will
use the actual terminal width as a display limit
unless 72 < DOCRT < width. In that case, the display
limit will be DOCRT characters.
OUTPRINT...Disk file name in which to save the line printer output.
' ' => use scratch and print immediately for interactive
jobs - batch jobs use OUTPRINT = 'PRTFIL:BATCHjjj.nnn'
(jjj= job #, nnn = user #). When OUTPRINT is not blank,
multiple outputs are concatenated, and the file is not
actually printed.
BADDISK....The disk numbers to avoid for scratch files (sorting
tables mostly).
EXPLAIN SECTION