; DFTPL ;--------------------------------------------------------------- ;! plots DFT of a UV data set at arbitrary point versus time ;# Task Plot UV ;----------------------------------------------------------------------- ;; Copyright (C) 1995, 2000, 2008-2009, 2014, 2016-2017 ;; Associated Universities, Inc. Washington DC, USA. ;; ;; This program is free software; you can redistribute it and/or ;; modify it under the terms of the GNU General Public License as ;; published by the Free Software Foundation; either version 2 of ;; the License, or (at your option) any later version. ;; ;; This program is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public ;; License along with this program; if not, write to the Free ;; Software Foundation, Inc., 675 Massachusetts Ave, Cambridge, ;; MA 02139, USA. ;; ;; Correspondence concerning AIPS should be addressed as follows: ;; Internet email: aipsmail@nrao.edu. ;; Postal address: AIPS Project Office ;; National Radio Astronomy Observatory ;; 520 Edgemont Road ;; Charlottesville, VA 22903-2475 USA ;----------------------------------------------------------------------- DFTPL LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC DFTPL Plots the DFT of an arbitrary point using UV data USERID -32000.0 32000.0 File owner number - ignored 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 # UVRANGE 0.0 Range of projected spacings (thousands of wavelengths) TIMERANG Time range to select: Start Day, Hour, Min, Sec End Day, Hour, Min, Sec SHIFT Shift in asec at ref position STOKES I, Q, U, V, RR, LL, XX, YY BPARM Control parameters 1 : unused 2 : averaging interval (sec) 3 : > 0.0 => fixed scale < 0.0 => fixed range 4 : Xmin (fixed scale) 5 : Xmax (fixed scale) 6 : Ymin (fixed scale) 7 : Ymax (fixed scale) 8 : X/Y axis ratio 9 : 1 plots points only 2 plots points and error bars 3 plots histogram 10 : scale factor for points SOURCES Source name QUAL -10.0 Calibrator qualifier -1=>all CALCODE Calibrator code ' '=>all SELBAND Bandwidth to select (kHz) SELFREQ Frequency to select (MHz) FREQID 0.0 Frequency ID number: 0 -> 1 SUBARRAY 0.0 1000.0 Sub-array, 0=>all BIF 0.0 First IF to include EIF 0.0 Last IF to include BCHAN 0.0 First channel to include ECHAN 0.0 Last channel to include 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. DOCIRCLE -1.0 1.0 > 0 => extend ticks to form coordinate grid PRTLEV -1.0 > 0 => print time, flux, and error to message file LTYPE -410.0 410.0 Type of labeling: 1 border, 2 no ticks, 3 - 6 standard, 7 - 10 only tick labels <0 -> no date/time DOTV -1.0 1.0 > 0 Do plot on the TV, else make a plot file GRCHAN 0.0 8.0 Graphics channel 0 => 1. ---------------------------------------------------------------- DFTPL Type: Task Use: Plots the DFT of the complex visibilities found in a UV data base for an arbitrary point in the sky as a function of time. Note that the visibilies are shifted under control of SHIFT and then the real parts are simply summed over all baselines in each time interval. Task TBAVG makes a UV data set of the summed visibilities instead of plotting them. NOTE: This task does NOT apply any flag or calibration tables. Run SPLIT or other appropriate task before running DFTPL. Adverbs: USERID.....Input file user number. Ignored 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. UVRANGE....Range (min, max) of projected baselines to include 0,0 => all baselines TIMERANG...Time range of the data to be plotted. In order: Start day, hour, min, sec, End day, hour, min, sec. Days relative to reference date. 0 => full range. SHIFT......Shift in arcseconds - the data are shifted, summed, and then plotted. These are shifts in arc seconds at the reference point - RA = RA0 + SHIFT(1)/cos(DEC0), DEC = DEC0 + SHIFT(2) STOKES.....Only one Hermitian polarization is allowed: I, Q, U, V, RR, LL, XX, YY. Cross-hands do not have the Hermitian property and so are not allowed. BPARM......Control parameters: 1: unused 2 = averaging interval in seconds (0 => 60) NOTE: an interval beginning at a sample time T1 will include all samples < T1+BPARM(2). If your data occur at 5 second intervals and you want no averaging, set BPARM(2) < 5. If you want to average pairs of samples, set 5 < BPARM(2) < 10. 3 = if greater than zero, use BPARM(4) - BPARM(8) as the ranges of the axes. If less than zero, use the BPARMs to limit the range of the axes, but self-scale the axes within that range. If 0.0, fully self-scaling. 4 = Minimum of X-axis. Units = days. 5 = Maximum of X-axis (if = BPARM(4) do self-scale in X). 6 = Minimum of Y-axis. Units = Jy. 7 = Maximum of Y-axis (if = BPARM(6) do self-scale in Y). 8 = Ratio of X axis length to Y axis length. 9 = If 1, simply plot up the point -1, plot points and print out results (0 => -1) If 2, plot points and error bars -2, plot points, error bars, and print out results If 3, plot points in histogram form -3, plot histogram and print out results SOURCES....Source to be copied. ' '=> all; if any starts with a '-' then all except ANY source named. NOTE: this task makes sense only if you select a single source. QUAL.......Qualifier of source to be processed. -1 => all. CALCODE....Calibrator code of source to be processed. ' '=> all. 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 process. 0=>all (okay if not calibration) BIF........Also average IFs BIF-EIF; 0 -> 1 EIF........Also average IFs BIF-EIF; 0 -> max BCHAN......Average channels BCHAN-ECHAN; 0 -> 1 ECHAN......Average channels BCHAN-ECHAN; 0 -> max 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). DOCIRCLE...False (<= 0) means that tick marks are short lines extending inward from the plot borders. True (>0) requests that a full coordinate grid be drawn. PRTLEV.....> 0 -> print time, flux, and dispersion to message file. LTYPE.......Labelling type, see HELP LTYPE for details: 1 = border, 2 = no ticks, 3 or 7 = standard, 4 or 8 = relative to ref. pixel, 5 or 9 = relative to subimage (BLC, TRC) center, 6 or 10 = pixels. 7-10 all labels other than tick numbers and axis type are omitted. Less than 0 is the same except that the plot file version number and create time are omitted. Add n * 100 to alter the metric scaling. DOTV.......> 0 => plot directly on the TV device, otherwise make a plot file for later display on one or more devices (including the TV if desired). GRCHAN.....Graphics channel (1 - 7) to use for line drawing. 0 => 1. ---------------------------------------------------------------- DFTPL: Plots DFT using data from a u,v data base. PROGRAMMER: T.Bastian, Univ. of Colorado RELATED PROGRAMS: TKPL,PRTPL,TVPL COMMENTS DFTPL was written primarily to assist stellar observers interested in time variable phenomena (e.g., outbursts on RS CVn's, dMe flare stars, etc.). Since these stars are in general unresolved, it's often pointless to make a synthesis map for each time interval. Instead one can do the following: 1) make a large field map using the entire XY sorted data base and identify all background sources; 2) run APCLN or MX with boxes around these sources (but not the stellar source of interest) and CLEAN them down to the noise; 3) using the resulting CLEAN components as a model of the background sources, use UVSUB to subtract the model from the UV data base; 4) use UVSRT to sort the data into TB order. If NO confusing sources of any importance can be found in the field, then of course steps 1-4 can be skipped and one simply begins with a TB sorted (calibated and edited) data base. he UV data base on an EXPORT tape is sorted in TB order, but one might have to use the verb PUTHEAD to indicate this fact in the header. This is done by first setting KEYWORD to 'SORT' and KEYSTRING to 'TB' and typing PUTH. The task DFTPL allows one to plot the direct fourier transform of the measured visibilities as a function of time for an arbitrary shift in RA and DEC. It will plot either points, points with error bars, or histogram format. The averaging interval is adjustable (BPARM(2)). The data time segment may be specified (through APARM). The task runs somewhat faster than UVPLT. Hence one can moniter all Stoke's parameters of a star with time VERY quickly, without having to resort to generating a tedious sucession of maps.