NAME

       CPSPS2 - Interpolates from an array of data on a "sparse" rectangular grid which is irregularly spaced in
       X and Y to an array of data on a "dense" rectangular grid and initializes contouring from the array on
       the dense grid. (By a "sparse" grid is meant one whose dimensions are smaller than one would like, so
       that contour lines constructed directly on it are composed of long straight segments.) CPSPS2 may be
       viewed as a data smoothing routine.

SYNOPSIS

        CALL CPSPS2 (XSPS, YSPS, ZSPS, KSPS, MSPS, NSPS, RWRK,
       + LRWK, IWRK, LIWK, ZDAT, LZDT)

C-BINDING SYNOPSIS

       #include <ncarg/ncargC.h>

       void c_cpsps2 (float *xsps, float *ysps, float *zsps,
       int ksps, int msps, int nsps, float *rwrk, int lrwk,
       int *iwrk, int liwk, float *zdat, int lzdt)

DESCRIPTION

       XSPS        (REAL  array,  dimensioned  MSPS)  is the array of X coordinates of the irregular rectangular
                   grid. These must be in strictly increasing numerical order.

       YSPS        (REAL array, dimensioned NSPS) is the array of Y coordinates  of  the  irregular  rectangular
                   grid. These must be in strictly increasing numerical order.

       ZSPS        (REAL  array, dimensioned KSPS x n, where "n" is greater than or equal to NSPS, input) is the
                   "sparse" array of data, from which the "dense" array is to be generated.

       KSPS        (INTEGER, input) is the first dimension of the array ZSPS.

       MSPS        (INTEGER, input) is the first dimension of the "sparse" array of data in ZSPS. MSPS  must  be
                   less than or equal to KSPS.

       NSPS        (INTEGER,  input) is the second dimension of the "sparse" array of data in ZSPS. NSPS must be
                   less than or equal to the declared second dimension of the array ZSPS.

       RWRK        (REAL array, dimensioned LRWK, input/output) is the real work array.

       LRWK        (INTEGER, input) is the length of RWRK.

       IWRK        (INTEGER array, dimensioned LIWK, input/output) is the integer work array.

       LIWK        (INTEGER, input) is the length of IWRK.

       ZDAT        (REAL array, dimensioned LZDT, output) is the array in which the interpolated  "dense"  array
                   of  data  is  to be returned. The dimensions of the interpolated array may be supplied by the
                   user or determined by Conpack, depending on the value of the parameter 'ZDS'. Note  that,  if
                   Conpack  determines  the  dimensions  of  the "dense" array, it will attempt to use an aspect
                   ratio which is close to that implied by the value of the ratio

                        (XSPS(MSPS)-XSPS(1))/(YSPS(NSPS)-YSPS(1))

       LZDT        (INTEGER, input) is the length of ZDAT.

C-BINDING DESCRIPTION

       The C-binding argument descriptions are the same as the FORTRAN argument descriptions, with the following
       exceptions:

       zsps(l,ksps)
                   Dimensioned l by ksps, where l ≤ nsps.

       ksps        The second dimension of the array zsps.

       msps        The second dimension of the sparse array of data in zsps. msps ≤ ksps.

       nsps        The first dimension of the sparse array of data in  zsps.   nsps  ≤  l,  the  declared  first
                   dimension of the array zsps.

USAGE

       CPSPS2  performs  the  same functions as CPRECT, but, in addition, it interpolates from a sparse array of
       data to a dense array of data.  CPSPS2 does this by using the routines SURF1 and SURF2, from the  package
       Fitpack,  by  Alan  K.  Cline,  to  fit  bicubic splines under tension to the sparse array of data and to
       compute the dense grid of data that is returned to you.  The tension on the spline surfaces is  specified
       by  the  parameter  'T3D'.   By  default,  CPSPS2  selects  the dimensions of the dense array of data; if
       desired, you can specify these dimensions by setting the parameter  'ZDS'  non-zero  and  the  parameters
       'ZD1', 'ZDM', and 'ZDN' to the desired values. In either case, once 'ZD1', 'ZDM', and 'ZDN' are set, they
       should  not  be  reset  by  you  until the contour plot is complete and a different contour plot is to be
       drawn.

       Because the routines SURF1 and SURF2 do not have a built-in special value feature, if the  special  value
       parameter  'SPV'  is set non-zero and the sparse array contains occurrences of that value, special action
       must be taken.  The indices of the special values in the sparse array are saved in a part of the  integer
       workspace  array;  the  special values are then replaced by values interpolated from adjacent grid points
       and the resulting array is used to obtain the dense array; then, the special values in the  sparse  array
       are restored and the corresponding elements of the dense array are also given the special value.

EXAMPLES

       Use the ncargex command to see the following relevant example: ccpsps2.

ACCESS

       To  use CPSPS2 or c_cpsps2, 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, cppkcl, cppklb,
       cprect, cprset, cpscae, cpsetc, cpseti, cpsetr, cpsps1, 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.

UNIX                                               March 1993                                     CPSPS2(3NCARG)