NAME

cxPyrLayerSkip - returns a cxConnection structure relating two non-adjacent pyramid layers
#include <cx/Pyramid.h>

cxConnection *cxPyrLayerSkip(cxPyramid *pyr, int src, int dst, int flag)
integer function cxPyrLayerSkip(pyr,src,dst,flag)
integer pyr
integer src
integer dst
integer flag
pyr
Input pyramid data structure.
src
Input index of the source layer.
dst
Input index of the destination layer.
flag
Input Boolean indicating the action to take when src equals dst.
The return value for this function is a pointer to a cxConnection structure that relates elements of two non-adjacent layers. cxPyrLayerSkip returns a cxConnection structure that relates the elements of layer src to the connections of layer dst. Equivalently, the returned cxConnection structure relates the elements of layer src to the elements of layer dst - 1, or to the base lattice, if dst is zero. cxPyrLayerSkip is useful for extracting from a fully populated pyramid a reduced structure that skips over unnecessary, intermediate layers. However, this does not change the restriction that all pyramids are expected to have fully formed intermediate layers. Thus cxPyrLayerSkip is only used when manipulating a pyramid within a module. The following C code example produces the connections from 3-D elements to 0-D nodes in a finite element pyramid:
  conn = cxPyrLayerSkip( pyr, 2, 0, 1 );
If src and dst are equal (and if flag is zero), the returned value is a copy of
  pyr->layer[src].relation.
The value of src must be greater than or equal to dst. If src is out of range, a NULL pointer is returned. The returned object should be properly freed after use with a call to cxDataRefDec to avoid memory leaks. cxDataRefDec(3E)
Last modified: Mon Nov 6 16:33:45 GMT 2000
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© The Numerical Algorithms Group Ltd, Oxford UK. 1996