; EVAUV ;----------------------------------------------------------------------- ;! Subtracts & divides a model into UV data, does statistics on results ;# TASK UV IMAGING MODELING CALIBRATION ;----------------------------------------------------------------------- ;; Copyright (C) 2009-2010, 2012, 2014-2015 ;; 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 ;----------------------------------------------------------------------- EVAUV LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC EVAUV does statistics on comparison of model and uv data INNAME Input UV file name (name) INCLASS Input UV file name (class) INSEQ 0.0 9999.0 Input UV file name (seq. #) INDISK Input UV file disk unit # NMAPS 0.0 4096.0 No. maps to use for model. NGAUSS 0.0 Number Gaussians in NMAPS IN2NAME Cleaned map name (name) IN2CLASS Cleaned map name (class) IN2SEQ 0.0 9999.0 Cleaned map name (seq. #) IN2DISK Cleaned map disk unit # INVERS -1.0 46655.0 CC file version #. BCOMP First CLEAN comp to sub. 1 per field. NCOMP Last CLEAN comp to sub. to use (0 => all) FLUX Lowest CC component used. CMETHOD Modeling method: 'DFT','GRID',' ' SMODEL Source model, 1=flux,2=x,3=y See HELP SMODEL for models. (1) not 0 -> ignore IN2NAME DOOUTPUT -1.0 1.0 > 0 save the UV files from model subtraction & division OUTNAME Output files name OUTSEQ Output files sequence OUTDISK Output files disk DOPLOT > 0 => plot Re vs Im maps = 2 => plot histograms too APARM 2-D Re/Im plot controls PIXRANGE Intensity range to use FUNCTYPE 'LG' use logarithms in plot of image intensities LTYPE type of labeling DOTV > 0 use TV, else plot file GRCHAN TV graphics channel to use BADDISK Disks to avoid for scratch @ Output adverbs RPARM @ Results (see help) ---------------------------------------------------------------- EVAUV Task: Subtracts and divides a model into a uv data base. The model may be a specific model, a set of CLEAN components files, or a set of images. "CLEAN" models may be points, Gaussians or uniform, optically thin spheres. The task will compute the model and then both subtract it from the input UV data and divide it into the UV data. It then reports on statistical attributes of the two data sets. The mean and rms of the real and imaginary parts and the amplitude are reported for the model subtracted data set and for the divided data set (after a constant 1.0 is subtracted from the real part). The amplitude mean is computed in a robust fashion and controls which samples enter into the real and imaginary part averages. Then the number of samples more than 3 rms away from the mean amplitude, the total number of samples, and the average of the absolute difference of the bad samples and the mean are reported. The model will use Clean Components if they are present and otherwise will do the image. No correction for convolution by the Clean Beam (if any) are made in the latter case. Offset sub-images are not supported. Following the UV analysis, the robust mean and rms over the images are determined and reported. Note that this mean and rms should omit any real source signals. Model images made with both values of IMAGR's DO3DIMAG option are handled correctly, as are multi-scale images. Set NMAPS = NFIELD * NGAUSS. EVAUV works only on single-source files. NOTE: this task does NOT apply flagging or calibration tables to the input UV data. Run SPLIT first if that operation is desired. Sample output: -------------- Image mean -7.3490E-07 rms 1.5078E-04 method real part imaginary part amplitude subtract 0.0002 +- 0.157 0.0002 +- 0.157 0.1977 +- 0.103 divide-1 -0.0040 +- 6.770 0.0017 +- 6.770 7.9390 +- 5.364 method # bad samples total samples avg bad amp subtract 79124 5333006 0.3918 divide-1 267058 5333006 27.1805 -------------- The optional plots are 1. The average and rms of the model subtracted data in bins of UV-plane radius. 2. The average and rms of the model divided - 1.0 data in bins of UV-plane radius. 3. The histogram of image pixels over a pixel value range selected by the user or the first of the model images. 4. The histogram of image pixels over a pixel range of plus/minus 5 times the rms of the first of the model images. 5. The real vs imaginary visibilities of the model subtracted data over a range of APARM(1) times the amplitude rms. The plot is a contour in logarithmic intervals of the 2-D histogram image controlled by APARM. Contours are drawn at 0.5, 1, 1.5, 2, 2.5, 3, etc in the log of the counts. 6. The real and imaginary gains minus (1,0) of the model divided data over a range of APARM(2) times the amplitude rms. Logarithmic contours also. Actually plots 5 and 6 cover somewhat larger areas but some data samples will not be plotted (totals on and off the plot are reported). 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. NMAPS......Number of image files to use for model. For multi-scale models, set NMAPS = NFIELD * NGAUSS to include the Clean components of the extended resolutions. If more than one file is to be used, the NAME, CLASS, DISK and SEQ of the subsequent image files will be the same as the first file except that the LAST 3 or 4 characters of the CLASS will be an increasing sequence above that in IN2CLASS. Thus, if INCLASS='ICL005', classes 'ICL005' through 'ICLnnn' or 'ICnnnn', where nnn = 5 + NMAPS - 1 will be used. Old names (in which the 4'th character is not a number) are also supported: the last two characters are '01' through 'E7' for fields 2 through 512. In old names, the highest field number allowed is 512; in new names it is 4096. NGAUSS.....Number of Gaussians in NMAPS. IN2NAME....Model map name (name). Standard defaults. IN2CLASS...Model map name (class). Standard defaults. IN2SEQ.....Model map name (seq. #). 0 => highest. IN2DISK....Disk drive # of model map. 0 => any. WARNING: SMODEL overrides the above model map specification. INVER......CC file ver. number. 0 => highest. BCOMP......The first clean component to process. One value is specified for each field used. NCOMP......Number of Clean components to use for the model, one value per field. If all values are zero, then all components in all fields are used. If any value is not zero, then abs(NCOMP(i)) (or fewer depending on FLUX and negativity) components are used for field i, even if NCOMP(i) is zero. If any of the NCOMP is less than 0, then components are only used in each field i up to abs(NCOMP(i)), FLUX, or the first negative whichever comes first. If abs(NCOMP(i)) is greater than the number of components in field i, the actual number is used. For example NCOMP = -1,0 says to use one component from field one unless it is negative or < FLUX and no components from any other field. This would usually not be desirable. NCOMP = -1000000 says to use all components from each field up to the first negative in that field. NCOMP = -200 100 23 0 300 5 says to use no more than 200 components from field 1, 100 from field 2, 23 from field 3, 300 from field 5, 5 from field 6 and none from any other field. Fewer are used if a negative is encountered or the components go below FLUX. FLUX.......Only components > FLUX in absolute value are used in the model. CMETHOD....This determines the method used to compute the model visibility values. 'DFT' uses the direct Fourier transform, this method is the most accurate. 'GRID' does a gridded-FFT interpolation model computation ' ' allows the program to use the fastest method. NOTE: data in any sort order may be used by the 'DFT' method but only 'XY' sorted data may be used by the 'GRID' method. NOTE: CMETHOD='GRID' does not work correctly for RL and LR data; DO NOT USE CMETHOD='GRID' for RL, LR! SMODEL.....A single component model to be used instead of a CLEAN components model; if abs (SMODEL) > 0 then use of this model is requested. SMODEL(1) = flux density (Jy) SMODEL(2) = X offset in sky (arcsec) SMODEL(3) = Y offset in sky (arcsec) SMODEL(4) = Model type: 0 => point model 1 => elliptical Gaussian and SMODEL(5) = major axis size (arcsec) SMODEL(6) = minor axis size (arcsec) SMODEL(7) = P. A. of major axis (degrees) 2 => uniform sphere and SMODEL(5) = radius (arcsec) DOOUTPUT...> 0 => save the residual (data minus model) and gain (data divided by model) files as cataloged files. <=0 => delete these files at the end of the task. OUTNAME....Output files name (name). ' ' -> INNAME The classes will be EVAUVS and EVAUVD for subtracted and divided data sets. OUTSEQ.....Output files name (seq #). 0 -> next highest OUTDISK....Output files disk number. 0 -> highest with space. DOPLOT.....> 0 => Plot the two real versus imaginary histogram images as contour maps with contours in the log at intervals of 0.5, 1, 1.5, 2.0, 2.5 etc > 1.5 => Also plot two plots showing the mean and rms residual and (gain-1) versus baseline length and two plots of the image histogram. <= 0 => no plots APARM......The real parts of the model subtracted and model divided data are plotted against the corresponding imaginary parts in two contour plots of the 2-D histogram images. The contour intervals are 0.5 in the logarithm of the counts in each cell of the images. APARM controls the extent of these images, their size, and whether they are smoothed: (1)....The model subtracted data are plotted over a range of +/- APARM(1) times the subtracted amplitude rms. 0 -> 5 (2)....The model divided data are plotted over a range of +/- APARM(1) times the divided amplitude rms. 0 -> 10 (3)....The plots are summed in images of APARM(3) pixels on a side. 0 -> SQRT (Nvis * Nchan / 10) <= 1024 (4)....The images are smoothed by a Gaussian kernel of APARM(4) pixels on a side before plotting. 0 -> no smoothing - will be set to an odd number <= 33. Hints: For large numbers of samples, you may wish to set APARM(1) and APARM(2) to higher numbers, e.g. 15 and 25 and you will want to smooth by e.g. 5 or 9 before plotting. For a small data set, a small image is a good idea. PIXRANGE...The range of image intensities to be used in the histogram that is intended to encompass the full interesting range of the image(s). 0 => use the range in the header of the first image. FUNCTYPE...'LG' => use logarithms in the plots of the image histograms, else do a linear plot. 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 on the TV, else make plot files. GRCHAN.....If plotting on the TV, use graphics plane GRCHAN. 0 => use more than one graphics plane, separating portions of the plot by color. BADDISK....The disk numbers to avoid for scratch files. RPARM......Output adverb with results ( 1, 2) Subtracted real part mean, rms ( 3, 4) Subtracted imag part mean, rms ( 5, 6) Subtracted ampl part mean, rms ( 7, 8) Subtracted fraction bad and average bad ( 9,10) Divided - 1 real part mean, rms (11,12) Divided - 1 imag part mean, rms (13,14) Divided - 1 ampl part mean, rms (15,16) Divided - 1 fraction bad and average bad (17,20) Image mean, rms of mean, rms, rms of rms (21,30) not used yet ----------------------------------------------------------------