External Interfaces Reference |
C Syntax
Arguments
array_ptr
Pointer to a sparse mxArray
.
Returns
A pointer to the first element in the ir
array, if successful, and NULL
otherwise. Possible causes of failure include:
mxArray
.
NULL
array_ptr
. (This usually means that an earlier call to mxCreateSparse
failed.)
Description
Use mxGetIr
to obtain the starting address of the ir
array. The ir
array is an array of integers; the length of the ir
array is typically nzmax
values. For example, if nzmax
equals 100, then the ir
array should contain 100 integers.
Each value in an ir
array indicates a row (offset by 1) at which a nonzero element can be found. (The jc
array is an index that indirectly specifies a column where nonzero elements can be found.)
For details on the ir
and jc
arrays, see mxSetIr
and mxSetJc
.
Examples
See fulltosparse.c
in the refbook
subdirectory of the examples
directory.
For additional examples, see explore.c
in the mex
subdirectory of the examples
directory; see mxsetdimensions.c
and mxsetnzmax.c
in the mx
subdirectory of the examples
directory.
See Also
mxGetJc
, mxGetNzmax
, mxSetIr
, mxSetJc
, mxSetNzmax
mxGetInf | mxGetJc |
© 1994-2005 The MathWorks, Inc.