NAME

cxLatCoordNew - create a lattice with coordinates and no data

C SPECIFICATION

#include <cx/DataAccess.h>

typedef enum {
 cx_coord_uniform,
 cx_coord_perimeter,
 cx_coord_curvilinear
} cxCoordType;

cxLattice *cxLatCoordNew(long nDim, long dims[],
   long nCoordVar, cxCoordType coordType)

FORTRAN SPECIFICATION

integer cx_coord_uniform
integer cx_coord_perimeter
integer cx_coord_curvilinear

parameter (cx_coord_uniform = 0)
parameter (cx_coord_perimeter = 1)
parameter (cx_coord_curvilinear = 2)

integer function cxLatCoordNew(nDim, dims, nCoordVar, coordType)
integer nDim, dims(nDim)
integer nCoordVar, coordType

PARAMETERS

nDim: Number of lattice dimensions.
dims: Array specifying length in each dimension.
nCoordVar: Number of elements per coordinate point.
coordType: Representation of coordinate information.

FUNCTION RETURN VALUE

Returns a pointer to a new lattice structure.

DESCRIPTION

cxLatCoordNew creates a cxLattice structure in data memory and returns a pointer it. The lattice created will have nDim dimensions; the length of each dimension is specified in the array dims. Coordinates of the type given by coordType will be created, with nCoordVar floating point elements per coordinate. nCoordVar does not have to be the same as nDim. For example, to create a two dimensional lattice representing a surface in a three dimensional space set nDim to 2 and nCoordVar to 3. No space for data will be allocated. See notes below.

Refer to "IRIS Explorer Module Writer's Guide" for more information on the structure of cxLattice and its contents.

Lattice data structures are allocated from a shared memory arena on Silicon Graphics workstations running IRIX. This shared memory is a limited resource, so it is possible for the memory to be exhausted, causing the allocation routine to fail. If the allocation routine fails, any memory it has successfully allocated will be released, and a NULL pointer will be returned. The subroutine cxDataAllocErrorGet returns TRUE if the lattice could not be allocated. See cxDataAllocErrorGet for more details on writing portable module code that copes well with limited memory.

NOTE

Many modules assume that a lattice has data. Modules built with the IRIS Explorer module builder utility (mbuilder(1)) also require that coordinates be present. It is strongly recommended that lattices be created with both data and coordinates for compatibility. cxLatCoordNew, used in conjunction with cxDataNew and cxLatPtrSet, allows the lattice, data and coordinates to be created separately.

Last modified: Mon Nov 18 13:50:15 GMT 1996
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