NAME

       Histogram_params - This document briefly describes all histogram internal parameters.  The Histogram
       utility has four parameter setting routines: HSTOPC sets parameters of type CHARACTER; HSTOPI sets
       parameters of type INTEGER; HSTOPL sets parameters of type LOGICAL; HSTOPR sets parameters of type REAL.

DESCRIPTION

       Parameters of type CHARACTER set in calls to entry HSTOPC:

       FOR         Format for class labels.  Default is ´(G10.3)´.

       TIT         A  main  title  of  up  to 96 characters.  Only 45 characters are written per line so up to 3
                   lines may be written.  The default is no title.

       LAB         A label for the class interval (histogram bar) axis.  Default value is ´CLASS INTERVALS´ when
                   the HSTOPL option ´MID=OFF´ is selected, and ´CLASS MIDVALUES´ when ´MID=ON´.

       PTI         The percent axis label.  Default value when ´PTI=OFF´ is ´PERCENT OCCURRENCE´ when IFLAG = 0,
                   or 1, and ´PERCENT of MAXIMUM´ when IFLAG = 2, or 3.

       FQN         The frequency axis label.  Default value is ´FREQUENCY´.

       CHR         A concatenated string of class interval  labels.   Default  is  that  class  labels  will  be
                   internally computed numeric values (real or integer.)

Parameters of type INTEGER set in calls to entry HSTOPI:

       COL         Eight  components  of  the graphic can be assigned colors.  Default is that all components of
                   the graphic are assigned the color white (background color black.)

       CLA         Allows the size and orientation of class labels to be altered.   Defaults  are  medium  sized
                   characters with a horizontal alignment.

Parameters of type LOGICAL set in calls to entry HSTOPL:

       HOR         Defines  whether histogram bars will be draw horizontally or vertically.  Default is vertical
                   bars.

       PER         Determines whether a percentage axis is drawn as a second axis on the opposite  side  of  the
                   frame from the normal frequency axis.  Default is a second axis.

       MID         Determines if class labels are placed at the midpoint of each class interval, or if the class
                   interval end points are labeled.  Default is labels at the midpoints.

       SHA         Determines whether histogram bars are to be shaded.  Default is shaded bars.

                   Devices will vary as to how they interpret shading.

       DRL         Determines  if lines are to be drawn through the histogram bars where Y-axis tick marks would
                   occur.  Default is no line.

       MED         Determines if a line is drawn through the median value of all points.  Default is  no  median
                   line.

       NMV         Determines  if missing values are to be subtracted from the number of input points before bin
                   percentages are computed.  The default is to subtract out the missing values.  HSTOPR  option
                   MVA must be ON to activate this option.

       PMV         Determines  if  the number of input points and the number of missing values are to be printed
                   on the plot.  The default is to not print.  HSTOPR option MVA must be  ON  to  activate  this
                   option.

       PRM         Determines if a perimeter is to be drawn around the histogram.  Default is no perimeter.

       FRA         Determines  whether  the  frame is advanced after the histogram is drawn.  Default is a frame
                   advance.

       LIS         Determines if all the options along with their values are  to  be  printed  on  the  standard
                   output.  Default is no printed output.

       DEF         A global default switch which allows all parameters to be returned to their default states in
                   one call.  All parameters begin at their default values.

Parameters of type REAL set in calls to entry HSTOPR:

       WIN         Defines a rectangular region of the total frame in NDC´s where the current histogram is to be
                   plotted.   For  example, XMIN=0., XMAX=.5, YMIN=.5, and YMAX=1.  would specify the upper left
                   quadrant of the frame.  Default is the total frame is used.

       SPA         Defines the amount of spacing between histogram  bars  and  and  the  amount  of  overlap  of
                   histogram  bars.   Default  values:  spacing  =  2.0,  overlap = -1.0 This will yield spacing
                   between bars on a single histogram and overlap of bars in the comparison of two histograms.

       MVA         Defines a special value which can be inserted in the data stream to indicate  that  the  true
                   data  value  is  missing,  and  a  testing  tolerance  which  allows the special values to be
                   detected.  See also parameters PMV,  and  NMV.   Default  values:  special  value  =  -9999.,
                   tolerance = 1.E-10.

SEE ALSO

       Online: histogram, histgr, hstopc, hstopi, hstopl, hstopr, ncarg_cbind

       Hardcopy: NCAR Graphics Fundamentals, UNIX Version

COPYRIGHT

       Copyright (C) 1987-2009
       University Corporation for Atmospheric Research

       The use of this Software is governed by a License Agreement.

UNIX                                               March 1993                           Histogram_params(3NCARG)