External Interfaces Reference |
Get number of elements in ir
, pr
, and pi
arrays
C Syntax
Arguments
array_ptr
Pointer to a sparse mxArray
.
Returns
The number of elements allocated to hold nonzero entries in the specified sparse mxArray
, on success. Returns an indeterminate value on error. The most likely cause of failure is that array_ptr
points to a full (nonsparse) mxArray
.
Description
Use mxGetNzmax
to get the value of the nzmax
field. The nzmax
field holds an integer value that signifies the number of elements in the ir
, pr,
and, if it exists, the pi
arrays. The value of nzmax
is always greater than or equal to the number of nonzero elements in a sparse mxArray
. In addition, the value of nzmax
is always less than or equal to the number of rows times the number of columns.
As you adjust the number of nonzero elements in a sparse mxArray
, MATLAB often adjusts the value of the nzmax
field. MATLAB adjusts nzmax
in order to reduce the number of costly reallocations and in order to optimize its use of heap space.
Examples
See mxgetnzmax.c
and mxsetnzmax.c
in the mx
subdirectory of the examples
directory.
See Also
mxGetNumberOfFields | mxGetPi |
© 1994-2005 The MathWorks, Inc.