CPCLDR - Draws contour lines.

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

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

       #include <ncarg/ncargC.h>

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

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

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

UNIX                                               March 1993                                     CPCLDR(3NCARG)

       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.

       Use  the ncargex command to see the following relevant examples: caredg, ccpcff, ccpcfx, ccpcica, ccpcir,
       ccpcis, ccpcit, ccpclc, ccpcld, ccpcldr, ccpcll, ccpclu, ccpdflt, ccpfil, ccpga, ccphand, ccphcf,  ccphl,
       ccphlt,  ccpila,  ccpilt,  ccpklb,  ccplbdr,  ccpline, ccpllp, ccpmap, ccpmovi, ccpmpxy, ccpncls, ccpnet,
       ccpnof, ccpnsd, ccppkcl, ccprect, ccprwc, ccprwu, ccpset, ccpsps1,  ccpsps2,  ccpspv,  ccpt2d,  ccptitle,
       ccpvp, ccpvs, cidsfft, cpex01, cpex05, cpex07, tconpa, fsfsgfa.

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

       CPCLDR - Draws contour lines.

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

       Hardcopy: NCAR Graphics Contouring and Mapping Tutorial

       CALL CPCLDR (ZDAT, RWRK, IWRK)

       The routine CPCLDR, which draws contour lines, may be called at any time after the initialization call to
       CPRECT, CPSPS1, or CPSPS2.  The contour lines drawn are those specified by the first  'NCL'  elements  of
       the parameter arrays 'CLV' and 'CLU'.  If 'NCL' is zero, CPPKCL is called to generate these values.  Each
       element  of  'CLV' specifies a contour level, and the corresponding element of 'CLU' specifies whether or
       not contour lines are to be drawn at that level and whether or not the lines are to be labeled.   If  the
       parameter 'T2D' has a non-zero value, the contour lines are smoothed, using cubic splines under tension.

       If the element of the parameter array 'CLU' corresponding to 'PAI' = -1 is non-zero, the edge of the grid
       is  also  drawn.   If the element of 'CLU' corresponding to 'PAI' = -2 is non-zero, the edges of special-
       value areas, if any, are drawn.  If the element of 'CLU' corresponding to 'PAI' =  -3  is  non-zero,  the
       edges of out-of-range areas, if any, are drawn.  The default values are such that none of these edges are
       drawn.

       Groups of lines are drawn in the following order:

       •  contour lines for each of the specified levels, in ascending numeric order,

       •  the edges of special-value areas, if any,

       •  the edges of out-of-range areas, if any, and

       •  the edge of the grid.

       The  color,  dash  pattern, and line width to be used for the lines drawn may be specified by elements of
       the  parameter  arrays  'CLC',  'CLD',  and  'CLL',  respectively.   Each  of  these  contains   elements
       corresponding to values of 'PAI' from 1 to 'NCL' and three special elements, corresponding to 'PAI' = -1,
       -2, and -3.  Before and after each group of lines is drawn, the routine CPCHCL is called.  You can supply
       your own version of CPCHCL to override the settings of color, dash pattern, and line width.

       The  dash-pattern-usage  parameter  ('DPU') affects the pattern used to draw the lines.  Set the value of
       'DPU' as follows:

       Value       Description

       < 0 or = 0  Lines are drawn by calling the SPPS routine  CURVE.   Lines  are  all  solid  and  unlabeled;
                   specified dash patterns are not used.

       > 0         Lines are drawn by calling the Dashline routine CURVED.  Lines are solid or dashed, depending
                   on the dash pattern specified by the appropriate element of 'CLD'.

                   If  ABS('LLP')  =  1,  then  the  dash  pattern  for  those  lines  that are to be labeled is
                   constructed by replicating, 'DPU' times,  the  dash  pattern  specified  by  the  appropriate
                   element  of  'CLD',  and  then  appending  to  it the characters specified by the appropriate
                   element of 'LLT'.

                   If ABS('LLP') is greater than 1, then the lines drawn will pass through any labels  drawn  by
                   CPLBDR.   If this is undesirable, you can call CPLBAM to put the label boxes into an area map
                   and then call CPCLDM instead of CPCLDR to draw only those portions of the contour lines which
                   do not lie inside the label boxes.

       If, during the last call to CPRECT or CPSPRS, the data being  contoured  were  found  to  be  essentially
       constant, then no contour lines are drawn; instead, the constant-field label is written.  Other lines are
       still drawn.