INNAME Input UV data INCLASS Input UV data (class) INSEQ Input UV data (seq. #) INDISK Input UV data disk drive # SOURCES Source (pointings) list QUAL -10.0 Source qualifier -1=>all CALCODE Calibrator code ' '=>all TIMERANG Time range to process. SELBAND Bandwidth to select (kHz) SELFREQ Frequency to select (MHz) FREQID Freq. ID to select. BIF 0.0 100.0 Lowest IF number 0=>all EIF 0.0 100.0 Highest IF number 0=>all BCHAN 0.0 2048.0 Lowest channel number 0=>all ECHAN 0.0 2048.0 Highest channel number 0=>all SUBARRAY 0.0 1000.0 Subarray, 0=>all DOCALIB -1.0 101.0 > 0 calibrate data & weights > 99 do NOT calibrate weights GAINUSE CL/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 OUTFGVER 0.0 Output FG 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. UVRANGE 0. Min & max baseline (klambda) SOLINT Time interval (sec) SCANLENG Scan length (sec) REFANT Reference antenna for VDIF OPTYPE Type of operation on the rms 'RFI ' 'HIST' 'ANTE' 'GAIN' 'VDIF' 'VRFI' 'TIME' is default DOCAT -1.0 1.0 > 0 => keep the XX file VECTOR -1.0 1.0 > 0 -> vector averaging <= 0 -> use amplitudes only DOROBUST -1.0 1.0 > 0 -> robust spectral avg BPARM (1) Fraction allowable ?? correlators (2) Fraction allowable ?? baselines (3) rms cutoff (Jy) for ??? (4) Amp. factor for cutoff (5) rms cutoff (Jy) for bad (6) Amp. factor for cutoff (7) Min hist level Jy for ??? (8) Min hist level Jy for bad (9) > 0 save 1-sample SOLINTs (10) best left <= 0. CPARM (1) Question if ampCPARM(2) (3) Flag if amp < CPARM(3) (4) Flag if amp > CPARM(4) (5) min amp rms allowed (6) min rms rms allowed (7) Question if amp > CPARM(7)*rms away from mean amplitude (8) Question if rms > CPARM(8)*(rms of rms's) away from mean rms (9) Flag if amp > CPARM(8)*rms away from mean amplitude. (10) Flag if rms > CPARM(10)*(rms of rms's) away from mean rms. DPARM (1) Question if wt DPARM(2) (3) Flag if wt < DPARM(3) (4) Flag if wt > DPARM(4) (5) Question if closure fraction > DPARM(5) (6) Flag if closure error fraction > DPARM(6) STOKES Correlators examined ' ' => RR/LL, XX/YY, I DOSTOKES -1.0 4.0 -1 flag only bad corr. 1 flag cross if parallel bad 2 flag parallel if cross bad 3 both 1 and 2 4 flag all Stokes if one bad 0 -> 3 DOIFS -1.0 1.0 > 0 -> flag all IFs if one is bad DOALL -1.0 1.0 > Flag all channels, else flag BCHAN - ECHAN DOCRT -3.0 132.0 > 0 -> use the terminal, > 72 => terminal width 0 -> no printing else use the line printer OUTPRINT Printer disk file to save PRTLEV > 0 => debug messages BADDISK -1.0 1000.0 Disks to avoid for scratch.

FLAGR Type: Task Use: This task computes the visibility amplitude and rms fluctuations in each baseline and correlator over a specified range of spectral channels and time. It can then convert the baseline-based quantities into apparent antenna-based quantities. In some of the OPTYPEs these are then compared with user-specified cutoffs. If a large enough fraction of the data are "questionable" then all of those data are flagged. If a given baseline/correlator or antenna/correlator is "bad", it will be flagged. A time-based OPTYPE saves the amplitudes and rmses and then reviews all of them over time, flagging discrepant ones on a source-by-source and antenna-by-antenna basis. Another time-based OPTYPE compares the complex visibilities on an antenna basis with the average of those in a range of time surrounding. Adverbs: INNAME.....Input UV data file INCLASS....Input UV data file (class). Standard defaults. INSEQ......Input UV data file (seq. #). 0 => highest. INDISK.....Input UV data file disk drive #. 0 => any. SOURCES....List of sources (pointings) to be processed. '*' or blank = all; a "-" before a source name means all except ANY source named. QUAL.......Only sources with a source qualifier number in the SU table matching QUAL will be used if QUAL is not -1. CALCODE...."sources" may be selected on the basis of the calibrator code given in the SU table. ' ' => any calibrator code selected '* ' => any non blank code (cal. only) '-CAL' => blank codes only (no calibrators) NB: The CALCODE test is applied in addition to the other tests, i.e. SOURCES and TIMERANG, in the selection of sources to process. CALCODE affects only the selection of calibrators. TIMERANG...Time range of the data to be processed. In order: Start day, hour, min. sec, end day, hour, min. sec. Days relative to reference date. 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 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. 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). BIF........First IF to select. 0=>all. EIF........Highest IF to select. 0=>all higher than BIF BCHAN......First channel to select. 0=>all. ECHAN......Highest channel to select. The spectral channels are used as separate samples of the visibility to provide better statistics in determining the rms. SUBARRAY...Subarray number to consider. 0=>1. GAINUSE....CL table version number to apply. 0=> highest. DOPOL......If > 0.5 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. OUTFGVER...Flag table version to be used on output for both single- and multi-source data sets. If OUTFGVER is <= 0 or greater than FGmax (the previously highest FG version number), then a new FG table will be created for the new flags with version FGmax+1. This new table will also contain the flags applied on input (if any) from FG version FLAGVER. If OUTFGVER specifies a pre-existing FG version, then the input flags are not copied even if OUTFGVER and FLAGVER are not equal. 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 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). UVRANGE....(Minimum,Maximum) baseline (kilo-lambda) to process. SOLINT.....The interval over which the rms is determined. 0 => 60 seconds. SCANLENG...Length of "scan" for VDIF and VRFI in seconds. The vector average of the visibilities over the scan is differenced from the individual visibility to make the "vector difference". REFANT.....Reference antenna suggestion for VDIF. OPTYPE.....Choice of operation to be performed: 'RFI ' -> acts similar to task RFI, flag all data for times when some fraction of baselines and correlators are excessively noisy, flag all of a correlator for times when some fraction of baselines are too noisy, and flag individual baselines at times when they are too noisy. 'HIST' -> like RFI above except that the histogram of all baselines for each correlator also yields a cutoff for those baselines wildly different from their fellows in addition to the cutoffs used in RFI. 'ANTE' -> Like RFI except that the baseline RMSes are converted to antenna RMSes before being checked for excess values. A robust method is used and closure failure statistics maintained. Data with excess closure failures are flagged along with those having amplitudes, rmses, and weights out of range. 'TIME' -> (default) Like ANTE it computes the antenna amplitudes and rmses in each SOLINT, but it simply saves them for later. A robust method is used and closure failure statistics maintained. When all data have been read, the antenna-based results are analyzed, source by source, antenna by antenna. Regression is used to compute the mean antenna amplitude and mean rms and the rmses in these parameters. Outliers are then flagged including those with excess closure failures. 'GAIN' -> Like TIME except that the source amplitudes are scaled by their average (over all data on that source) and then all sources are examined together. This may be needed when there is not much data on some of the sources making too few SOLINTs to determine robust averages on a source by source basis. One should do this only with calibrator sources of similar flux. 'VDIF' -> It computes the baseline reals, imaginaries, and weights in each SOLINT and converts then to antenna-based values. A robust method is used and closure failure statistics maintained. It saves them for later. When all data have been read, the antenna-based results are analyzed source by source, correlator by correlator. First the visbility at each time is differenced with the average of the visibilities surrounding it. The weights, amplitudes, and amplitudes of the differences are then used to flag the data as are the closure failure rates. 'VRFI' -> It computes the baseline reals, imaginaries, and weights in each SOLINT and saves as many as it can for later. When the source changes, the buffer is full, or all data have been read, the baseline-based results are analyzed correlator by correlator. First the visbility at each time is differenced with the average of the visibilities surrounding it. The weights, amplitudes, and amplitudes of the differences are then used to flag the data. DOCAT......> 0 => keep the XX extension file generated by the TIME and VDIF OPTYPEs. Otherwise delete it on exit. VECTOR <= 0 -> all averaging and rms's are computed using amplitudes only. Otherwise, the real and imaginary parts of the visibility are used. The former will be insensitive to phase variations, but have biased noise statistics. DOROBUST...> 0 => Do robust averaging of the spectral channels in each time and baseline. Normal averaging is done over time. <= 0 => Normal averaging (all samples included) is done over all channels as well as time. BPARM......Control parameters (1) If the fraction of all correlators regarded as questionable exceeds BPARM(1), flag all data for this integration period. 0 -> 0.51 All OPTYPEs. (2) If the fraction of baselines regarded as questionable exceeds BPARM(2), mark the particualr correlator as questionable and flag it (or all correlators - see BPARM(1) above). 0 -> 0.25 All OPTYPEs. (3) The maximum allowable sine/cosine rms per baseline and correlator to mark it as questionable. No default. For VDIF, the maximum allowable amplitude of the vector difference to mark questionable. Not used in OPTYPE='TIME'. Jy. (4) Source amplitude coefficient for determining questionable baselines. The maximum allowed rms or amplitude of the vector difference is given by: sqrt (BPARM(3)**2 + (avg_amp*BPARM(4))**2) Note: the value of BPARM(4) is a compromise between false detection of interference on strong sources and missing interference on weak sources as the interference may mimic a strong source. 0 -> 0.1. Not used in OPTYPE='TIME'. (5) The maximum allowable sine/cosine rms per baseline and correlator to flag that baseline. 0 -> BPARM(3). For VDIF, the maximum allowable amplitude of the vector difference to mark as bad. Not used in OPTYPE='TIME'. Jy. (6) Source amplitude coefficient like BPARM(4) but used to flag individual baselines rather than just mark them as questionable. 0 -> BPARM(4). Not used in OPTYPE='TIME'. (7) HIST only: Set the histogram flag level for questionable data to MAX (BPARM(7), histogram value). Thus, if the data are particularly noise free do not delete some anyway. Jy. No default. (8) HIST only: Set the histogram flag level for bad data to MAX (BPARM(8), histogram value). Thus, if the data are particularly noise free do not delete some anyway. Jy. 0 -> BPARM(7) (9) > 0 => do not flag correlators having only 1 sample in the integration period; <=0 => such orphans are deleted. RFI, HIST, ANTE, and TIME now include such orphans in the previous integration if possible and if all correlators are orphaned. If previous editing reduces some correlators to single samples, but not others, then the single-sample ones are flagged under control of BPARM(9). (10) unused CPARM......More control parameters: 1-4 for All OPTYPEs (1) Treat data with amplitude <= CPARM(1) as questionable. Jy. (2) Treat data with amplitude > CPARM(2) as questionable. Jy. (3) Treat data with amplitude <= CPARM(3) as bad. Jy. (4) Treat data with amplitude > CPARM(4) as bad. Jy. (5) 'TIME', 'GAIN' only: Limit the true rms in the amplitudes to be >= CPARM(5). Jy. (6) 'TIME', 'GAIN' only: Limit the true rms in the rmses to be >= CPARM(6). Jy. (7) 'TIME', 'GAIN' only: Question data more than CPARM(7) times the true rms away from the true mean. 0 -> 3.5 (8) 'TIME', 'GAIN' only: Question data with rms more than CPARM(8) times the true rms of the rms's over all antennas, IFs, and polarizations away from the true mean of those rms's. 0 -> 8. (9) 'TIME', 'gain' only: Flag data more than CPARM(9) times the true rms away from the true mean. 0 -> 7 (10) 'TIME', 'GAIN' only: Flag data with rms more than CPARM(10) times the true rms of the rms's over all antennas, IFs, and polarizations away from the true mean of those rms's. 0 -> 16. DPARM......(1) Question data with weight <= DPARM(1) in 1/Jy^2. (2) Question data with weight > DPARM(2) in 1/Jy^2. (3) Flag data with weight <= DPARM(1) in 1/Jy^2. (4) Flag data with weight > DPARM(2) in 1/Jy^2. (5) The antenna amplitudes are tested for closure error. If the difference of the baseline amplitude and the product of the antenna amplitudes exceeds 3 times the rms difference, a closure error is counted. For VDIF, the antenna-based complex solution is compared with the data and if the amplitude of the difference exceeds 2.5 times the rms of the differences, a closure error is counted. If the fraction of baselines involving an entenna with closure error is > DPARM(5) then the data for that antenna are questioned. 0 -> 0.5 (6) If the fraction of baselines with closure error is > DPARM(6), then that antenna is flagged. 0 -> 1 (i.e. no flagging). STOKES.....Which correlators will be examined: 'FULL', 'HALF', 'RR', 'LL', 'RRLL', 'RLLR', 'XX', 'YY', 'XXYY', 'XYYX' or a "bit pattern" '1111', '1110', etc. Note that input correlators are examined no Stokes conversion will take place. Only limited forms of the Stokes axis are supported other than through the bit pattern form. DOSTOKES...-1 => Flag only the bad correlator, no other +1 => Flag both cross-hand polarizations when one parallel-hand is bad +2 => Flag both parallel-hand polarizations when one cross-hand is bad +3 => +1 and +2 +4 => flag all correlators when one is bad 0 => +3 DOIFS......> 0 => flag all IFs if one is bad; else flag only the bad IF. DOALL......> 0 => flag all spectral channels; else flag only channels BCHAN through ECHAN. DOCRT......Zero means write the flag table without comment. 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. PRTLEV.... Set > 0 to get various debug level messages. Attached to the histogram finder and to the antenna-based solver. PRTLEV=3 gets failure information, =4 gets the results of the histogram and antenna based functions. In the finding of antenna-base complex "gains", PRTLEV=4 will show results of the fit and PRTLEV=5 will show the input data and the rms at each iteration. BADDISK....This array contains the numbers of disks on which it is desired that scratch files not be located.

See FINDR for a task to find typical values to guide you in using FLAGR. FINDR even returns typical values in adverb ARRAY2. Explanation of the methods used All OPTYPEs (so far) start by averaging the calibrated and flagged data over a period of SOLINT seconds. Data with a time difference <= SOLINT are included. Thus, a SOLINT of 60 with records every 10 seconds will include 7 records; to get only 6 set SOLINT to something > 50 and < 60 such as 55. The data from each included antenna pair, IF, and polarization are kept separate, but the spectral channels from BCHAN through ECHAN are averaged together. For OPTYPEs RFI, HIST, ANTE, GAIN, and TIME: During the averaging, the apparent rms is found including all data (no outlier rejection). The rms and amplitude are averaged by vector means unless BPARM(10) > 0, in which case scalar amplitudes are used. For OPTYPEs VDIF and VRFI: The averaging is done to determine the "individual" records to be compared with the "scan" averages of such records in a region of time centered on the individual records. Typically, with decent signal-to-noise, one will set SOLINT for VDIF to less than the time between records. The "scan" averaging is done over the scan interval using parameter SCANLENG and is done by finding the median real and imaginary parts which should be less sensitive to outliers. If PRTLEV=1, the task prints messages about "bad" samples. If PRTLEV=2, it also prints messages about "questionable" samples. Even with PRTLEV=0, messages about antenna-independent flags are printed. A summary of generated flags is printed at the end. Note that DOCRT=0, suppresses all printing although the flag counts will go to the message file in that case. At this point, the OPTYPEs do somewhat different things: =============== OPTYPE 'RFI ' The task loops over all antenna pairs, IFs, and polarizations counting the "questionable" data. A sample is questionable if Sig(A1,A2,I,P)^2 > BP(3)^2 + (BP(4) * Amp(A1,A2,I,P))^2 or Amp(A1,A2,I,P) <= CP(1) or Amp(A1,A2,I,P) > CP(2) or Wt(A1,A2,I,P) <= DP(1) or Wt(A1,A2,I,P) > DP(2) where Sig(A1,A2,I,P) is the rms of the antenna pair A1 and A2 at IF I, polarization P, Amp is the average amplitude of the sample, Wt is the average weight of the sample, BP(*) is BPARM(*), CP(*) is CPARM(*), and DP(*) is DPARM(*). Looping over all IFs and polarizations, the task counts the number of antenna pairs that are questionable. If the fraction of questionable pairs exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antenna pairs) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antenna pairs and flags any that are "clearly bad", i.e. that have Sig(A1,A2,I,P)^2 > BP(5)^2 + (BP(6) * Amp(A1,A2,I,P))^2 or Amp(A1,A2,I,P) <= CP(3) or Amp(A1,A2,I,P) > CP(4) or Wt(A1,A2,I,P) <= DP(3) or Wt(A1,A2,I,P) > DP(4) =============== OPTYPE 'HIST' The task loops over all antenna pairs, IFs, and polarizations counting the "questionable" data. A sample is questionable if Sig(A1,A2,I,P)^2 > BP(3)^2 + (BP(4) * Amp(A1,A2,I,P))^2 or Sig(A1,A2,I,P)^2 > Max (BP(7), HistClip(I,P))^2 or Amp(A1,A2,I,P) <= CP(1) or Amp(A1,A2,I,P) > CP(2) or Wt(A1,A2,I,P) <= DP(1) or Wt(A1,A2,I,P) > DP(2) where Sig(A1,A2,I,P) is the rms of the antenna pair A1 and A2 at IF I, polarization P, Amp is the average amplitude of the sample, BP(*) is BPARM(*), CP(*) is CPARM(*), and DP(*) is DPARM(*). HistClip is determined from the histogram of rms's for each antenna pair and is set to delete <= 6 per cent of the rms's or all rms's more than 3 sigma from the mean rms. BPARM(7) keeps this from getting too small when the data are nearly perfect. Looping over all IFs and polarizations, the task counts the number of antenna pairs that are questionable. If the fraction of questionable pairs exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antenna pairs) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antenna pairs and flags any that are "clearly bad", i.e. that have Sig(A1,A2,I,P)^2 > BP(5)^2 + (BP(6) * Amp(A1,A2,I,P))^2 or Sig(A1,A2,I,P)^2 > Max (BP(8), HistClip(I,P))^2 or Amp(A1,A2,I,P) <= CP(3) or Amp(A1,A2,I,P) > CP(4) or Wt(A1,A2,I,P) <= DP(3) or Wt(A1,A2,I,P) > DP(4) =============== OPTYPE 'ANTE' The task converts the average amplitudes, rms's, and weights of the antenna pairs into antenna-based values using the assumption that Amp(A1,A2,I,P) = SQRT (Amp(A1,I,P) * Amp(A2,I,P)) Sig(A1,A2,I,P) = SQRT (Sig(A1,I,P) * Sig(A2,I,P)) Wt(A1,A2,I,P) = SQRT (Wt(A1,I,P) * Wt(A2,I,P)) It uses robust methods (outliers ignored) to compute the antenna-based values and then counts the fraction [Fr(A,I,P)] of baselines for each antenna that are more than 3 times the rms away from the final solution. The task then loops over all antennas, IFs, and polarizations counting the "questionable" data. A sample is questionable if Sig(A,I,P)^2 > BP(3)^2 + (BP(4) * Amp(A,I,P))^2 or Amp(A,I,P) <= CP(1) or Amp(A,I,P) > CP(2) or Wt(A,I,P) <= DP(1) or Wt(A,I,P) > DP(2) or Fr(A) > DP(5) where Sig(A,I,P) is the rms of antenna A at IF I, polarization P, Amp is the average amplitude of the sample, BP(*) is BPARM(*), CP(*) is CPARM(*), and DP(*) is DPARM(*). Looping over all IFs and polarizations, the task counts the number of antennas that are questionable. If the fraction of questionable antennas exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antennas) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antenna pairs and flags any that are "clearly bad", i.e. that have Sig(A,I,P)^2 > BP(5)^2 + (BP(6) * Amp(A,I,P))^2 or Amp(A,I,P) <= CP(3) or Amp(A,I,P) > CP(4) or Wt(A,I,P) <= DP(3) or Wt(A,I,P) > DP(4) or Fr(A) > DP(6) =============== OPTYPE 'TIME' The default. The task converts the average amplitudes, rms's, and weights of the antenna pairs into antenna-based values using the assumption that Amp(A1,A2,I,P) = SQRT (Amp(A1,I,P) * Amp(A2,I,P)) Sig(A1,A2,I,P) = SQRT (Sig(A1,I,P) * Sig(A2,I,P)) Wt(A1,A2,I,P) = SQRT (Wt(A1,I,P) * Wt(A2,I,P)) It uses robust methods (outliers ignored) to compute the antenna-based values and then counts the fraction [Fr(A,I,P)] of baselines for each antenna that are more than 3 times the rms away from the final solution. The values of Amp(A,I,P), Sig(A,I,P), Wt(A,I,P) and Fr(A,I,P) are then written to an XX table (which may be saved by setting DOCAT > 0). When all of the data have been read and averaged and the antenna-based results written to the XX table, these results are read back into memory. One source at a time, the task determines the robust average amplitude and robust average rms (along with the uncertainties in these robust averages) for each antenna, IF, and polarization. By "robust" average, we mean an average determined by repeated passes through the data with the averaging process discarding outlier points. The robust average of these robust averages is then determined and printed in the message window. The robust average is computed only for those amplitudes between CPARM(1) and CPARM(2). For each source and one antenna, IF, and polarization at a time, the task loops over time counting the "questionable" data. A sample is questionable if Wt(A,I,P,t) <= DP(1) or Wt(A,I,P,t) > DP(2) or Fr(A,I,P,t) > DP(5) or Amp(A,I,P,t) <= CP(1) or Amp(A,I,P,t) > CP(2) or ABS(Amp(A,I,P,t)-AvAmp(A,I,P)) > CP(7)*MAX (CP(5), AvAmprms(A,I,P)) or Sig(A,I,P,t)-AvSig(A,I,P) > CP(8) * AvAvRms where Sig(A,I,P,t) is the rms of antenna A at IF I, polarization P, time t; Amp(A,I,P,t) is the average amplitude of that sample, AvAmp(A,I,P) is the robust average over time of that antenna, IF, and polarization, AvAmprms(A,I,P) is the uncertainty in that average over time, AvSig(A,I,P) is the robust average over time of the rms's of that antenna, IF, and polarization, and AvAvRms is the robust average over all antennas, IFs, and polarizations of AvSig, CP(*) is CPARM(*), and DP(*) is DPARM(*). Looping over all IFs and polarizations, the task counts the number of antennas that are questionable at the time in question. If the fraction of questionable antennas exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antennas) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antennas and flags any that are "clearly bad", i.e. that have Wt(A,I,P,t) <= DP(3) or Wt(A,I,P,t) > DP(4) or Fr(A,I,P,t) > DP(6) or Amp(A,I,P,t) <= CP(3) or Amp(A,I,P,t) > CP(4) or ABS(Amp(A,I,P,t)-AvAmp(A,I,P)) > CP(9)*MAX (CP(5), AvAmprms(A,I,P)) or Sig(A,I,P,t)-AvSig(A,I,P) > CP(10) * AvAvRms =============== OPTYPE 'GAIN' The task converts the average amplitudes, rms's, and weights of the antenna pairs into antenna-based values using the assumption that Amp(A1,A2,I,P) = SQRT (Amp(A1,I,P) * Amp(A2,I,P)) Sig(A1,A2,I,P) = SQRT (Sig(A1,I,P) * Sig(A2,I,P)) Wt(A1,A2,I,P) = SQRT (Wt(A1,I,P) * Wt(A2,I,P)) It uses robust methods (outliers ignored) to compute the antenna-based values and then counts the fraction [Fr(A,I,P)] of baselines for each antenna that are more than 3 times the rms away from the final solution. The values of Amp(A,I,P), Sig(A,I,P), Wt(A,I,P) and Fr(A,I,P) are then written to an XX table (which may be saved by setting DOCAT > 0). When all of the data have been read and averaged and the antenna-based results written to the XX table, these results are read back into memory. The task determines the relative Flux(s) of each source s averaging ALL values of Amp(A,I,P,t) by source. The "gains" are then Gn(A,I,P,t) = Amp(A,I,P,t) / Flux(s) Using all sources, the task determines the robust average gain and robust average rms (along with the uncertainties in these robust averages) for each antenna, IF, and polarization. By "robust" average, we mean an average determined by repeated passes through the data with the averaging process discarding outlier points. The robust average of these robust averages is then determined and printed in the message window. The robust average is computed only for those amplitudes between CPARM(1) and CPARM(2). One antenna, IF, and polarization at a time, the task loops over time counting the "questionable" data. A sample is questionable if Wt(A,I,P,t) <= DP(1) or Wt(A,I,P,t) > DP(2) or Fr(A,I,P,t) > DP(5) or Amp(A,I,P,t) <= CP(1) or Amp(A,I,P,t) > CP(2) or ABS(Gn(A,I,P,t)-AvGn(A,I,P)) > CP(7)*MAX (CP(5), AvGnrms(A,I,P)) or Sig(A,I,P,t)-AvSig(A,I,P) > CP(8) * AvAvRms where Sig(A,I,P,t) is the rms of antenna A at IF I, polarization P, time t; Amp(A,I,P,t) is the average amplitude of that sample; Gn(A,I,P,t) is the average gain of that sample; AvGn(A,I,P) is the robust average over time of that antenna, IF, and polarization, AvGnrms(A,I,P) is the uncertainty in that average over time; AvSig(A,I,P) is the robust average over time of the rms's of that antenna, IF, and polarization, and AvAvRms is the robust average over all antennas, IFs, and polarizations of AvSig, CP(*) is CPARM(*), and DP(*) is DPARM(*). Looping over all IFs and polarizations, the task counts the number of antennas that are questionable at the time in question. If the fraction of questionable antennas exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antennas) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antennas and flags any that are "clearly bad", i.e. that have Wt(A,I,P,t) <= DP(3) or Wt(A,I,P,t) > DP(4) or Fr(A,I,P,t) > DP(6) or Amp(A,I,P,t) <= CP(3) or Amp(A,I,P,t) > CP(4) or ABS(Gn(A,I,P,t)-AvGn(A,I,P)) > CP(9)*MAX (CP(5), AvGnrms(A,I,P)) Sig(A,I,P,t)-AvSig(A,I,P) > CP(10) * AvAvRms =============== OPTYPE 'VDIF' The task converts the average weights and complex visibilities of the antenna pairs into antenna-based values using the assumption that Amp(A1,A2,I,P) = SQRT (Amp(A1,I,P) * Amp(A2,I,P)) Phs(A1,A2,I,P) = Phs(A1,I,P) - Phs(A2,I,P) Wt(A1,A2,I,P) = SQRT (Wt(A1,I,P) * Wt(A2,I,P)) It uses robust methods (outliers ignored) to compute the antenna-based values and then counts the fraction [Fr(A,I,P)] of baselines for each antenna that are more than 2.5 times the rms away from the final solution. The values of Amp(A,I,P), Phs(A,I,P) (as real and imaginary), Wt(A,I,P), Fr(A,I,P), and reference antennas (I,P) are then written to an XX table (which may be saved by setting DOCAT > 0). When all of the data have been read and averaged and the antenna-based results written to the XX table, these results are read back into memory. If needed, the data are put on a consistent reference antenna basis. One source at a time, the task then loops over each antenna, IF, and polarization converting the time sequence of reals and imaginaries into time sequences of amplitudes and amplitudes of the "vector difference" between the current antenna visibility and the vector average of antenna visibilities within SCANLENG/2 of the current time. Note that, in this case, the averages are generated by finding the median value of the reals and the median value of the imaginaries. This should be somewhat less succeptible to outliers than straight averaging and better than robust averaging as well for the small number of samples which will be normal. For each source and one antenna, IF, and polarization at a time, the task loops over time counting the "questionable" data. A sample is questionable if Wt(A,I,P,t) <= DP(1) or Wt(A,I,P,t) > DP(2) or Fr(A,I,P,t) > DP(5) or Amp(A,I,P,t) <= CP(1) or Amp(A,I,P,t) > CP(2) or Dif(A,I,P,t) > BP(3) + (BP(4) * Amp(A,I,P)) where Dif(A,I,P,t) is the amplitude of the vector difference of antenna A at IF I, polarization P, time t with the average of the data within SCANLENG/2 of t; Amp(A,I,P,t) is the average amplitude of that sample, BP(*) is BPARM(*), CP(*) is CPARM(*), and DP(*) is DPARM(*). Looping over all IFs and polarizations, the task counts the number of antennas that are questionable at the time in question. If the fraction of questionable antennas exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antennas) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antennas and flags any that are "clearly bad", i.e. that have Wt(A,I,P,t) <= DP(3) or Wt(A,I,P,t) > DP(4) or Fr(A,I,P,t) > DP(6) or Amp(A,I,P,t) <= CP(3) or Amp(A,I,P,t) > CP(4) or Dif(A,I,P) > BP(5) + (BP(6) * Amp(A,I,P)) =============== OPTYPE 'VRFI' The task accumulates SOLINT averages in memory until the source changes, the data ends, or the number of times that it can hold is exhausted. For each time, the task then loops over each antenna pair, IF, and polarization finding the amplitude of the "vector difference" between the current visibility and the vector average of visibilities for that antenna pair within SCANLENG/2 of the current time. Note that, in this case, the averages are generated by finding the median value of the reals and the median value of the imaginaries. This should be somewhat less succeptible to outliers than straight averaging and better than robust averaging as well for the small number of samples which will be normal. The task loops over all antenna pairs, IFs, and polarizations counting the "questionable" data. A sample is questionable if Dif(A1,A2,I,P) > BP(3) + (BP(4) * Amp(A1,A2,I,P)) or Amp(A1,A2,I,P) <= CP(1) or Amp(A1,A2,I,P) > CP(2) or Wt(A1,A2,I,P) <= DP(1) or Wt(A1,A2,I,P) > DP(2) where Dif(A1,A2,I,P) is the amplitude of the vector difference of the antenna pair A1 and A2 at IF I, polarization P, Amp is the average amplitude of the sample, Wt is the average weight of the sample, BP(*) is BPARM(*), CP(*) is CPARM(*), and DP(*) is DPARM(*). Looping over all IFs and polarizations, the task counts the number of antenna pairs that are questionable. If the fraction of questionable pairs exceeds BPARM(2), then that IF/polarization is "bad". If the number of correlators (1 IF with 1 polarization all antenna pairs) that are bad divided by the total number of correlators exceeds BPARM(1), then all data for that period are "bad". The task then makes flags for these two types of badness and can print information about them. The task then loops over all remaining antenna pairs and flags any that are "clearly bad", i.e. that have Dif(A1,A2,I,P) > BP(5) + (BP(6) * Amp(A1,A2,I,P)) or Amp(A1,A2,I,P) <= CP(3) or Amp(A1,A2,I,P) > CP(4) or Wt(A1,A2,I,P) <= DP(3) or Wt(A1,A2,I,P) > DP(4) The task then loops for the new source and/or a new buffer load as appropriate until the data are exhausted.