; EVASN ;--------------------------------------------------------------- ;! Evaluates statistics in SN/CL tables ;# Task UV Calibration ;----------------------------------------------------------------------- ;; Copyright (C) 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 ;----------------------------------------------------------------------- EVASN LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC EVASN: evaluates statistics in SN/CL tables 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 INEXT Input'SN' or 'CL' table INVERS Input table file version no. SOURCES Source list QUAL -10.0 Source qualifier -1=>all TIMERANG Time range to consider STOKES Stokes type to consider SELBAND Bandwidth to include (kHz) SELFREQ Frequency to include (MHz) FREQID Freq. ID to include, -1=>all BIF 0.0 100.0 First IF to consider, 0=>1. EIF 0.0 100.0 Last IF to consider SUBARRAY 0.0 Subarray to consider: 0 ->1 ANTENNAS Antennas to consider 0=>all CUTOFF Table weight below which data will not be considered, 0 => consider all. DPARM Control parameters (1) max acceptable deviation from mean gain amplitude in (robust) rms's (2) min acceptable cos of Delta phase ---------------------------------------------------------------- EVASN Type: Task Use: Examines the statistics in an SN or CL table. It determines the mean and rms of the amplitude of the gain in a robust fashion and then determines the number and level of outliers. It examines the decorrelation on baselines due to the changes in phase between calibrations. All sources may be considered in SN tables (or limited with the SOURCES adverb) but only sources with a non-blank CALCODE will be examined in CL tables. Note that similar considerations may be used in SNFLG to flag the observations. 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. INEXT......'SN' or 'CL' table to be consider INVERS.....Version number of table to consider, 0=>highest no. SOURCES....Source list. '*' = all; a "-" before a source name means all except ANY source named. 'ALL' means to ignore the source identifier in the SN/CL table and combine all of them into one "source". QUAL.......Only sources with a source qualifier number in the SU table matching QUAL will be used if QUAL is not -1. TIMERANG...Time range of the data to be considered. In order: Start day, hour, min. sec, end day, hour, min. sec. Days relative to reference date. STOKES.....The desired Stokes type to be considered 'R' = RCP, 'L' = LCP, else the phase difference of R and L is treated as the data for JUMP or the ratio of R and L gains is treated as the data for AMP. 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. 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 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. -1 => all, 0 => first BIF........Lowest IF to consider. 0 -> 1 EIF........Highest IF to consider. 0 -> highest ANTENNAS...A list of the antennas to be considered. All 0 => all. If any number is negative then all antennas listed are NOT to be considered and all others are. CUTOFF.....If >= 0, the task will examine the weight column of the table and if the weight < CUTOFF, the task will consider that sample to be bad. All samples with weight <= 0 are considered bad. An FG table entry will be generated for the time surrounding a bad solution. DPARM......(1) View as "excess" and gain amplitudes that differ from the robust mean gain solution be more than DPARM(1) times the robust rms on a per source, antenna, IF, and polarization basis. 0 -> 6 The robust mean gain amplitude and its rms are reported as a function of IF and polarization. The fraction of samples having excess amplitude and the average of that excess (in rms's) are reported. (2) Gain phases are examined between the current and previous solution time on a per source, antenna, IF, and polarization basis. If the cosine of the difference in phase is < DPARM(2), then the correlation is viwed as low. >= 1, <= -1, 0.0 -> 0.5 Then mean and rms correlation are reported as a function of IF and polarization. Note that a correlation of 1.0 is full correlation (Delta phase = 0). The fraction of samples having a low correlation and the average of those samples are reported. ----------------------------------------------------------------