; UVIMG ;--------------------------------------------------------------- ;! Grid UV data into an "image" ;# TASK UV IMAGING ;----------------------------------------------------------------------- ;; Copyright (C) 1995, 1997, 2000, 2003-2004, 2006, 2009 ;; 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 ;----------------------------------------------------------------------- UVIMG LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC UVIMG: Task to grid UV data into an "image" INNAME UV data (name). INCLASS UV data (class). INSEQ 0.0 9999.0 UV data (seq. #). 0 => high INDISK Disk unit #. 0 => any OUTNAME Image data (name). OUTCLASS Image data (class). OUTSEQ 0.0 9999.0 Image data (seq. #). 0=>high OUTDISK Disk unit #. 0 => any SOURCES Source list TIMERANG Time range to list STOKES Stokes type to list. SELBAND Bandwidth to select (kHz) SELFREQ Frequency to select (MHz) FREQID Freq. ID to select. BIF 0.0 100.0 Lowest IF number 0=1 EIF 0.0 100.0 Highest IF number BCHAN 0.0 2048.0 Low channel number 0=>1 ECHAN 0.0 2048.0 High channel number ANTENNAS Antennas to list BASELINE Baselines with ANTENNAS UVRANGE 0.0 UV range in kilolambda SUBARRAY 0.0 1000.0 Subarray, 0=>1 Cal. info for input: 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. 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. DPARM Control info: (1) 0=amp, 1=phase, 2=rms, 3=rms/mean, 4=real part, 5=imaginary. (2) 0=vec avg, 1=scalar (3) >0 = baseline as ant pair for B as x-axis only (4) >0 => divide by source IPOL flux (5) x-axis interval: is B for TB and is ignored, else is the 2nd sort parameter NO default. Units: seconds, wavelengths (6) y-axis interval: T for TB first sort parameter NO default IMSIZE 1.0 8192.0 Output image size in x,y x ignored if B BADDISK Disk to avoid for scratch. ---------------------------------------------------------------- UVIMG Type: Task Use: Grids UV data of the selected type to form an image. UVIMG will work on single- and multi-source files in any sort order. It grids the data by the sort parameters with the 2nd (faster) parameter on the x axis and the 1st (slower) parameter on the y axis. All samples falling into a cell are averaged by vector or scalar averaging. Each included channel and IF is gridded to a separate plane of the output 3- or 4-dimensional image. 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. OUTNAME....Image file name (name). Standard defaults. OUTCLASS...Image file name (class). Standard defaults. OUTSEQ.....Image file name (seq. #). 0 => highest. OUTDISK....Output disk unit #. Standard defaults. SOURCES....List of sources to be gridded. ' '=> all; if any starts with a '-' then all except ANY source named. For OPTYPE='GAIN' this controls the sources in the SN or CL table to be listed. TIMERANG...Time range of the data to be gridded. In order: Start day, hour, min., sec, end day, hour, min., sec. in days relative to reference date. STOKES.....The desired Stokes type of the gridded data ' ' => 'I'. 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 occasionally result in an ambiguity, in which case the task will request that you use FREQID. BIF........Lowest IF to grid. IF will be axis 4. ************************************************** NOTE to VLA users: IF=1 corresponds to the VLA AC ifpairs and IF=2 corresponds to the BD ifpairs. ************************************************** EIF........Highest IF to grid. 0 => highest. BCHAN......First channel to grid in axis 3. 0 => 1. ECHAN......Last channel to grid. 0 => highest. ANTENNAS...A list of the antennas to grid. If any number is negative then all antennas listed are NOT desired and all others are. All 0 => grid all. BASELINE...Baselines are specified for the LIST option using BASELINE. Eg. baselines 1-6,1-8, 2-6 and 2-8 use ANTENNAS=1,2; BASELINE=6,8. UVRANGE....Range of projected spacings to be gridded in 1000's of wavelengths. 0 => 1, 1.E10 SUBARRAY...Subarray number to grid. 0=>1. 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). MUST be false for single-source data in BT order. 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 table. Only one subarray may be done at a time. 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. 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 BP correction. 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). DPARM......Control info: (1) controls the type of information to be gridded: 0 => amplitude, 1 => phase, 2 => RMS of amplitude 3 => RMS of amplitude / mean of amplitude 4 => real part of visibility 5 => imaginary part of visibility (2) controls the type of averaging: <= 0 => vector average, > 0 => scalar averaging (amplitude only). (3) controls how "baseline number" is computed <= 0 => normal baselines (1-2, 1-3, ... 1-N, 2-3, 2-4, ... 2-N, 3-4, ...) > 0 => as antenna pair gridding each sample twice (1-2, 1-3, ... 1-N, 2-1, 2-3, ... 2-N, 3-1, 3-2, ... 3-N, ...) (4) <= 0 => grid amplitudes as found in data set > 0 => divide amplitudes by source flux (5) X-axis interval: NO default except 1.0 is forced for B type axis. Units are wavelengths for U, V, W, X, Y, Z, and M sort orders and seconds for T. (6) Y-axis interval: NO default except 1.0 is forced for B type axis. Units are wavelengths for U, V, W, X, Y, Z, and M sort orders and seconds for T. IMSIZE.....X,Y output image size, no sensible default except for B type axis. BADDISK....Disk numbers to avoid for scratch files. Scratch files may be created by the sorting routines if calibration or flagging is applied. ----------------------------------------------------------------