NAME

       HSTOPC - Specifies various CHARACTER variables to be used by the Histogram utility.

SYNOPSIS

       CALL HSTOPC (STRING,STRNG2,NUMBER,ILCH)

C-BINDING SYNOPSIS

       #include <ncarg/ncargC.h>

       void c_hstopc (char *string, char *strng2, int number,
       int ilch)

DESCRIPTION

       STRING      Character, input -- Selects an internal parameter.  The possibilities are:

                     ´FOR=ON´ or ´FOR=OFF´
                     ´TIT=ON´ or ´TIT=OFF´
                     ´LAB=ON´ or ´LAB=OFF´
                     ´PTI=ON´ or ´PTI=OFF´
                     ´FQN=ON´ or ´FQN=OFF´
                     ´CHR=ON, or ´CHR=OFF´

                   If an option is turned ´ON´ then the STRNG2, NUMBER, and ILCH arguments can be
                   used to override the default settings of that option.

                   If the value of a STRING option is ´OFF´ then the next three arguments of the
                   HSTOPC call can be any dummy value.  Option settings will be returned to their
                   default values.

                   The following options are defined by this subroutine:

                   FOR     Format for class labels.  The ´FOR=OFF´ default is
                            ´(G10.3)´. Although class values are real numbers, integer formats
                           are allowed, in which case HISTGR will convert from real to integer
                           before plotting labels.

                   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 ´TIT=OFF´ default is no
                           title.

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

                           In order to delete this axis label, select ´LAB=ON´ for STRING and
                           ´NOLABEL´ for STRNG2.

                   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.  The ´FQN=OFF´ default value is ´FREQUENCY´.

                           In order to delete this axis label, select ´FQN=ON´ for STRING and
                           ´NOLABEL´ for STRNG2.

                   CHR     A concatenated string of alphanumeric class interval labels.  The
                           default value is a set of internally computed numeric class labels.

       STRNG2      Character, input -- A string of up to 45 characters.

                    ´FOR=ON´, STRNG2 is a format for the class labels.

                    ´TIT=ON´, STRNG2 is a histogram main title.

                    ´LAB=ON´, STRNG2 is a label for the class interval axis.

                    ´PTI=ON´, STRNG2 is a label for the percentage axis.

                    ´FQN=ON´, STRNG2 is a label for the frequency axis.

                    ´CHR=ON´, STRNG2 is a concatenated string of class labels.

                   The length of this character string will be NUMBER*ILCH, where NUMBER is the
                   number of class intervals and ILCH is the number of characters in the interval
                   label.

       NUMBER      Integer, input -- It only applies to the following options:

                    ´FOR=ON´, NUMBER specifies the maximum number of class intervals (histogram
                   bars) that will be labeled.  The default values (´FOR=OFF´) are 9 labels for
                   vertical bars and 15 labels for horizontal bars.

                    ´CHR=ON´, NUMBER must be set to NCLASS, an argument of the next call to be
                   made to routine HISTGR.

                   NUMBER is not used under any other option setting.

                   Calls to HSTOPC with either ´FOR=ON´ or ´CHR=ON´ may be performed in any
                   order; the parameters set by NUMBER are mutually exclusive.

       ILCH        Integer, input -- It only applies in the following instance.

                   If ´CHR=ON´, ILCH specifys the number of characters in each label of a class
                   interval (histogram bar).   ILCH cannot be greater than 15.

C-BINDING DESCRIPTION

       The C-binding argument descriptions are the same as the FORTRAN argument descriptions.

USAGE

       HSTOPC is called to set parameters of type CHARACTER before entry HISTGR is called to
       generate the histogram.  Options are main and axes titles, class interval (bar) labels,
       and class interval formats.

       For a complete list of parameters available in this utility, see the histogram_params man
       page.

EXAMPLES

       Use the command "ncargex thstgr" to generate a three frame example of histogram options.
       The following code causes the second frame to have a class interval axis of 12 intervals,
       each with a 3 character label that specifies a month of the year.

       PARAMETER (NCLASS=12, ILCH=3)
       CHARACTER*55 MON
       MON=´JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC´
       CALL HSTOPC(´CHR=ON´,MON,12,3)

       Example  "ncargex thstmv" shows three examples of histograms with missing values in the
       input data.

ACCESS

       To use HSTOPC or c_hstopc, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c,
       preferably in that order.

MESSAGES

       See the histogram man page for a description of all Histogram error messages and/or
       informational messages.

SEE ALSO

       Online: histogram, histogram_params, histgr, 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.