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Basic Information on imhist

Task: imhist
Purpose: plot a histogram of the data
Categories: map analysis

   Imhist makes histograms of image data. The output can be written to
   the terminal, a log file, or a plot.
   A gaussian curve with the same mean, rms and integral is drawn in
   the histogram (this can be turned off using the 'nogauss' option).
   The plotheader can be suppressed by using options=noheader. An
   alternative title can be put on the plot by options=title. A useful
   combination is 'options=noh,t,title', to get only the string 'title',
   instead of the full header.

Key: in
   Standard keyword in. See the help on in for more information.

Key: region
   Standard keyword region. See the help on region for more information.
   For the moment imhist only recognizes rectangular boxes.

Key: options
   These options allow to control the plot. They may be abbreviated to
   uniqueness. Several options may be combined, in random order.
   Possible options are (# means: give a number):
    'nbin,#'      Select the number of bins of the histogram, default 25
    'binsize,#'   Select a fixed size for the bins
    'cumulative'  Make the histogram cumulative
    'logarithmic' Make the y-scale of the histogram logarithmic
    'nogauss'     Do not plot the smooth gaussian curve
    'noheader'    Do not write the header information, just the numbers,
                  producing an ASCII file for a plotting program
    'nolist'      Do not write the statistics to the screen/logfile
    'ymax,#'      The plot will be cut off at this y-value, default
                  is 1.25 times maximum histogram value
    'title,#1,#2,#3' Put the string #1 at x-position #2 and y-position #3,
                  with positions measured in units of the coordinates
                  on the axes. If 'title' is the last option, the title
                  is put in the upper left hand corner.
    'style,#'     This selects the plot style.
                  #=connect means connect the datapoints
                  #=step means make one-bin wide connected horizontal
                  line segments
                  #=histo means bins are drawn as a horizontal line
                  surrounded by two vertical lines

Key: cutoff
   All datavalues below the cutoff are not used for the calculation of
   the histogram. Give one real value, which may be followed by the
   string ',abs' to get a cutoff in the absolute value of the datavalues.
   Default is no cutoff.

Key: xrange
   This gives two numbers, being the acceptable datavalues to include
   in the statistics and histogram.
   This is, in effect, the opposite of cutoff.
   Specifying both cutoff and xrange is possible. In this case,
   the two constraints are 'and-ed' together to determine which
   data are to be included. The xrange key alone, however, defines the
   xrange of the plot axis.

Key: device
   Standard keyword device. See the help on device for more information.

Key: log
   If specified, output is written to the file given by log= instead
   of to the terminal.
Revision: 1.5, 2016/09/13 23:30:14 UTC

Generated by miriad@atnf.csiro.au on 14 Sep 2016