NAME

cxConnEleGet - return connections of one element from a connection list structure

C SPECIFICATION

#include <cx/DataAccess.h>

cxErrorCode cxConnEleGet(cxConnection *src, long index,
long *numConnections, long **connections)

FORTRAN SPECIFICATION

integer function cxConnEleGet(src, index, numconnections, pconnections)
integer src
integer index
integer numconnections
integer pconnections

pointer (pconnections, connections)
integer connections(numconnections)

PARAMETERS

src: Input connection list data structure.
index: Input number of the element whose connections are to be returned.
numConnections: Output length of the connections array.
connections: Output pointer to the array of all connections (represented by the index number of the connection's destination) for the lattice element indicated by index.

FUNCTION RETURN VALUE

The return value for this function is an integer error code enumeration.

DESCRIPTION

cxConnEleGet returns the integer number of connections associating the element numbered index to elements in the next lower pyramid layer. index uses a one-based indexing scheme, so that the first element is numbered one, rather than zero. It also returns a pointer to an allocated vector into which the connection destinations of element index have been copied.

The user is responsible for freeing the connections array after use. The connections array is allocated using malloc, rather than the shared memory allocation routines.

If cxConnEleGet is to be called many times to extract all the connection information from a connection list, it is usually many times faster to make a single call to cxConnPtrGet, which returns pointers to the actual connection list arrays.

The Fortran user can access the connections array by using the Fortran Pointer construction to equivalence the returned integer memory address and the start of the desired array, as indicated in the Fortran specification above.

A return value of cx_err_none indicates success, while another value indicates a malformed input connection list, an invalid index, or a memory allocation error.