; SNFIT
;---------------------------------------------------------------
;! Fits parabola to SN amplitudes and plots result
;# Task UV Calibration Plot
;-----------------------------------------------------------------------
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;;
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;-----------------------------------------------------------------------
SNFIT     LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
SNFIT:  Task to fit parabolas or 4th order to SN amplitudes
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
INVERS                             Input table file version no.
SOURCES                            Source list
QUAL            -10.0              Source qualifier -1=>all
TIMERANG                           Time range to plot
STOKES                             Stokes type to plot: R, L,
                                      RR, LL, RRLL, DIFF, RATO
                                      X, Y, XX, YY, XXYY
SELBAND                            Bandwidth to plot (kHz)
SELFREQ                            Frequency to plot (MHz)
FREQID                             Freq. ID to plot, -1=>all
SUBARRAY         -1.0              Limit to subarray; 0 -> 1
                                      -1 -> all
BIF               0.0      100.0   First IF to plot, 0=>1.
EIF               0.0      100.0   Last IF to plot 0 -> highest
ANTENNAS                           Antennas to plot 0=>all
PIXRANGE                           Range to plot: 0 => self
                                   scale each antenna separately
NPLOTS            0.0      28.0    Number of plots per page
XINC              0.0     5000.0   Plot every XINC'th point
OPTYPE                             Data to be plotted:
                                   'AMP ','POWR','PODB'
                                   ' '='PODB'
APARM                              (1) Min value to fit
                                   (2) Max value to fit
                                   (3) =4 => use 4th order
                                      function
SYMBOL          0.0        24.0    Plot symbol number: 1 - 24
FACTOR        -10.0        10.0    Scale plot symbols by FACTOR
                                   <0 => connect points too
DOBLANK        -1.0        24.0    > 0, show blanked values with
                                   symbol type DOBLANK
CUTOFF                             Table weights <= CUTOFF will
                                   not be plotted, flagged data
                                   are not plotted.
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
OUTTEXT                            Not blank -> write text file
                                   with answers
----------------------------------------------------------------
SNFIT
Type:  Task
Use:   Plots selected calibration data versus time from a specified SN
       table and fits a 2nd order or 4th order polynomial to the gain
       amplitudes (as gain, power, or power in db).  This is to be
       used for scans through the primary beam on strong calibration
       sources.  Moving sources are supported if a PO table is
       attached.
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.
  INVERS.....Version number of table to plot, 0=>highest no.
  SOURCES....Source list.  '*' = 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.
  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.  If a start and stop time are given and
             the XAXIS is 1 (time), then all plots will be from the
             given start time to the given stop time.  Otherwise, the
             X-axis is plotted over the range of X values found in the
             data.  All plots in a given execution will be on the same
             X scale in any case.
  STOKES.....The desired Stokes type of the displayed data:
             'R' = RCP, 'L' = LCP, 'RL' or 'RRLL' both RCP and LCP
             'X' = XLP, 'Y' = YLP, 'XY' or 'XXYY' both XLP and YLP
  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
  SUBARRAY...Limit display to specific subarray.  -1 -> all, 0 -> 1.
  BIF........First IF IF to plot
  EIF........Last IF to plot.
             If OPCODE = 'IFDF'/'IFRA' will plot difference/ratio of
             specified quantity between BIF and EIF.
  ANTENNAS...A list of the antennas to be plotted. All 0 => all.  If any
             number is negative then all antennas listed are NOT to be
             plotted and all others are.
  PIXRANGE...If PIXR(1) < PIXR(2), all plots will be from PIXR(1) to
             PIXR(2).  Otherwise each plot will be self-scaling.
  NPLOTS.....Number of antennas to plot per page (try 5).
  XINC.......Plot every XINC'th point, 0 => 1.
  OPTYPE.....Data to be plotted:
             1.  'AMP ' = amplitude,
             2.  'POWR' = (1/Gain amp)^2
             3.  'PODB' = Log10 (1/Gain amp)^2
             other => 'PODB'
  APARM......(1) Lower limit of data to be used in the fit
             (2) Upper limit of data to be used in the fit
                 (APARM(2) <= APARM(1) -> all data are used)
             (3) If APARM(3) = 4, a fourth order function is fit,
                 otherwise a second order function is fit.
  SYMBOL.....1: Plus sign (default)   12: Five pointed star
             2: Cross (X)             13: Star of David
             3: Circle                14: Seven-pointed star
             4: Box                   15: Eight-pointed star
             5: Triangle              16: Nine-pointed star
             6: Diamond               17: Ten-pointed star
             7: Pentagon              18: 11-pointed star
             8: Hexagon               19: 12-pointed star
             9: Septagon              20: 13-pointed star
             10: Octagon              21: 14-pointed star
             11: Nine-gon             22: Plus with gap
                                      23: vertical line
                                      24: Cross with gap
  FACTOR.....Scale plot symbols by FACTOR     0 -> 1.
             If FACTOR < 0, draw lines between the points and use
             abs(FACTOR) to scale the points plotted.
  DOBLANK....> 0 => plot blanked solutions with a symbol of type
             DOBLANK (see symbol types above).  They will be plotted
             along the lower edge of each plot.  NOTE: if DOTV true
             and GRCHAN 0 and DO3COL <= 0, then the blanked samples
             will be in the color of graphics channel 3 (pink) and the
             good samples in the color of graphics channel 4 (blue).
             DOBLANK > 0 is forced to be different than SYMBOL by
             adding 1.
  CUTOFF.....If >= 0, the task will examine the weight column of the
             table and if the weight <= CUTOFF, the task will not plot
             that sample.  If = 0, will plot all good points; flagged
             data are not plotted.  CUTOFF is ignored for TY and PC
             tables and OPTYPEs MDEL, ATM, GEO, and CCAL.
  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.
             A value of 0 causes more than one graphics channel to be
             used.
  OUTTEXT....If not ' ', write the fit values to a text file.
----------------------------------------------------------------
