CSSGRIDD(3) tension spline interpolation on a sphere.

SYNOPSIS

CALL CSSGRIDD (N, RLAT, RLON, F, NI, NJ, PLAT, PLON, FF, IWK, RWK, IER)

DESCRIPTION

N
(integer,input) The number of input data points (N > 2).
RLAT
(double precision, input) An array containing the latitudes of the input data, expressed in degrees. The first three points must not be collinear (lie on a common great circle).
RLON
(double precision, input) An array containing the longitudes of the input data, expressed in degrees.
F
(double precision, input) An array containing data values. F(I) is a functional value at (RLAT(I),RLON(I)) for I = 1 to N.
NI
(integer, input) The number of rows in the uniform output grid. NI can be 1.
NJ
(integer, input) The number of columns in the uniform output grid. NJ can be 1.
PLAT
(double precision, intput) An array of length NI containing the latitudes the output grid lines. The values in PLAT should be in degrees.
PLON
(double precision, intput) An array of length NJ containing the longitudes the output grid lines. The value in PLON should be in degrees.
FF
(double precision, output) An NI by NJ array containing the desired interpolated values. FF(I,J) is the interpolated value at the coordinate specified by PLAT(I) and PLON(J) for I = 1 to NI and J = 1 to NJ.
IWK
(integer, input) An integer workspace of length 27*N.
RWK
(double precision, input) A work array dimensioned for 13*N. Note that RWK must be typed DOUBLE PRECISION.
IER
(integer, output) An error return value. If IER is returned as 0, then no errors were detected. If IER is non-zero, then refer to the man page for cssgrid_errors for details.

USAGE

CSSGRIDD is called to find an interpolating tension spline for data randomly positioned on a sphere. CSSGRIDD is a double precision version of CSSGRID.

ACCESS

To use CSSGRIDD, load the NCAR Graphics library ngmath.

COPYRIGHT

Copyright (C) 2000
University Corporation for Atmospheric Research

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