NAME

       CPPKCL - Picks a set of contour levels.

SYNOPSIS

       CALL CPPKCL (ZDAT, RWRK, IWRK)

C-BINDING SYNOPSIS

       #include <ncarg/ncargC.h>

       void c_cppkcl (float *zdat, float *rwrk, int *iwrk)

DESCRIPTION

       All three arguments are arrays used in the last call to CPRECT, CPSPS1, or CPSPS2, the
       contents of which must not have been changed since that call.

       ZDAT        (REAL array, dimensioned as specified in the last call to CPRECT, CPSPS1, or
                   CPSPS2, input) is the data array.

       RWRK        (REAL array, dimensioned as specified in the last call to CPRECT, CPSPS1, or
                   CPSPS2, input/output) is the real workspace array.

       IWRK        (INTEGER array, dimensioned as specified in the last call to CPRECT, CPSPS1,
                   or CPSPS2, input/output) is the integer workspace array.

C-BINDING DESCRIPTION

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

USAGE

       Normally, CPPKCL is called by CONPACK when the contour levels are needed; it may be called
       directly by the user when it is desired to modify the resulting parameter arrays
       specifying contour levels and associated quantities in some way.  CPPKCL must be called
       after initialization has been done (by a call to one of the initialization routines
       CPRECT, CPSPS1, or CPSPS2); this is because CPPKCL depends on values set during
       initialization.

       If the contour-level-selection parameter 'CLS' is zero (indicating that the user intends
       to pick contour levels), or if the constant-field-flag 'CFF' is non-zero (indicating that,
       during initialization, the data were found to be essentially constant), CPPKCL does
       nothing.  Otherwise, CPPKCL picks a set of contour levels.  The way in which it picks
       these levels is determined by the value of the internal parameter 'CLS'; see the
       description of this parameter in the conpack_params man page.

       When CPPKCL picks contour levels, it sets the value of the internal parameter 'NCL' equal
       to the number of contour levels picked.  It then sets the values of elements 1 through
       'NCL' of the parameter array 'CLV' (contour level values) to the levels chosen.  The Ith
       elements of the associated parameter arrays are set as follows:

       CLU = 1 or 3               Contour level use flag
       AIA = I+1                  Area identifier above the level
       AIB = I                    Area identifier below the level
       LLT = ' ' (single blank)   Contour line label text
       CLD = '$$$$$$$$$$$$$'      Contour line dash pattern
       CLC = -1                   Contour line color
       LLC = -1                   Contour line label color
       CLL = 0.                   Contour line line width

       Thus, after CPPKCL is called, the situation for each contour level is as follows:

       •      Contour lines at the level are to be drawn by calls to CPCLDM or CPCLDR.

       •      The lines will be labeled if 'CLU'=3, but not if 'CLU'=1.

       •      If CPCLAM is called, lines at the level will be added to the area map; the area
              identifiers for areas "above" the level and for areas "below" the level are as
              specified by 'AIA' and 'AIB'.

       •      The dash pattern for the level is solid, and neither the color of the line, the
              color of the labels on it, nor its width are to be set.

       •      The text of the label associated with the level is, as yet, unspecified.

       By resetting elements in these parameter arrays, the user can change the situation in
       various ways.

EXAMPLES

       Use the ncargex command to see the following relevant examples: ccpclc, ccpcld, ccpcldm,
       ccpcll, ccpklb, ccplbam, ccplbdr, ccpllb, ccpllc, ccplll, ccpllo, ccpllp, ccpllt, ccpllw,
       ccppc, ccppc1, ccppc2, ccppc3, ccppc4, ccppkcl, ccprc, ccprwc, ccpscam, cpex01, cpex02,
       cpex03, cpex06, vvex01, fcover, ffex03, ffex05.

ACCESS

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

MESSAGES

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

SEE ALSO

       Online: conpack, cpback, cpchcf, cpchcl, cpchhl, cpchil, cpchll, cpcica, cpclam, cpcldm,
       cpcldr, cpcltr, cpcnrc, cpdrpl, cpezct, cpgetc, cpgeti, cpgetr, cplbam, cplbdr, cpmpxy,
       cpmviw, cpmvrw, cppklb, cprect, cprset, cpscae, cpsetc, cpseti, cpsetr, cpsps1, cpsps2,
       ncarg_cbind

       Hardcopy: NCAR Graphics Contouring and Mapping Tutorial

COPYRIGHT

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

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