ncl_dsgrid2d - Man Page

double precision Fortran entry for iterpolation from 2D random data to an output grid.

Synopsis

CALL DSGRID2D (NPNTS, X, Y, Z, NUMXOUT, NUMYOUT, XO, YO, ZO, IER)

Description

NPNTS

(Integer, Input) - The number of input data points.

X

(Double precision, Input) - An array containing the  X coordinates of the input data points.

Y

(Double precision, Input) - An array containing the Y  coordinates of the input data points.

Z

(Double precision, Input) - An array containing the functional values  of the input data points. That is, Z(L) is the value of the input function at  coordinate (X(L),Y(L)), for L=1,NPNTS.

NUMXOUT

(Integer, Input) - The number of X values in the output grid.

NUMYOUT

(Integer, Input) - The number of Y values in the output grid.

XO

(Double precision, Input) - An array of dimension NUMXOUT containing the X  coordinates of the output data grid. The values in XO must be  increasing, but need not be equally spaced.

YO

(Double precision, Input) - An array of dimension NUMYOUT containing the Y  coordinates of the output data grid. The values in YO must be  increasing, but need not be equally spaced.

ZO

(Double precision, Output) -  A two-dimensional array of dimension NUMXOUT x NUMYOUT containing the interpolated functional values. ZO(I,J) is the interpolated value at grid point (XO(I),YO(J)).

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 dsgrid_errors for details.

Usage

DSGRID2D is the double precision gridding function for 2D data  in the Dsgrid package. The behavior of DSGRID2D is controlled by values set for the various parameters described in dsgrid_params.  Values for these parameters can be set using the subroutines DSSETI, DSSETRD, and DSSETC.

In almost all cases the ngmath function NATGRIDD is superior to DSGRID2D for 2D interpolation.  See the man page for NATGRIDD for details.

Access

To use DSGRID2D, load the NCAR Graphics library ngmath.

See Also

dsgrid, dsgrid_params,  dsseti,  dsgeti,  dssetrd,  dsgetrd,  dssetc,  dsgetc.

Complete documentation for Dsgrid is available at URL
http://ngwww.ucar.edu/ngdoc/ng/ngmath/dsgrid/dshome.html

Info

September 1997-1998 UNIX NCAR GRAPHICS