NAME

cxConnEleGet - return connections of one element from a connection list structure
#include <cx/DataAccess.h>

cxErrorCode cxConnEleGet(cxConnection *src, long index, long *numConnections, long **connections)
integer function cxConnEleGet(src, index, numconnections, pconnections)
integer src
integer index
integer numconnections
integer pconnections

pointer (pconnections, connections)
integer connections(numconnections)
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.
The return value for this function is an integer error code enumeration. 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.

The user can tell the function not to get information on a particular field by passing a NULL pointer value. You need not create dummy variables in the calling routine which calls cxConnEleGet, because the request is simply ignored when the pointer comes in NULL.

cxConnNew(3E), cxConnPtrGet(3E), cxConnEleSet(3E), malloc(3E)
Last modified: Mon Nov 6 16:32:58 GMT 2000
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© The Numerical Algorithms Group Ltd, Oxford UK. 1996

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