MATLAB Application Program Interface Reference | Help Desk |
mxGetN
Get the total number of columns in a two-dimensionalmxArray
or the total number of elements in dimensions 2 through N for an m-by-n array.
#include "matrix.h" int mxGetN(const mxArray *array_ptr);array_ptr The number of columns in the
mxArray
.
Call mxGetN
to determine the number of columns in the specified mxArray
.
If array_ptr
is an N-dimensional mxArray
, mxGetN
is the product of dimensions 2 through N. For example, if array_ptr
points to a four-dimensional mxArray
having dimensions 13-by-5-by-4-by-6, then mxGetN
returns the value 120 (5x4x6). If the specified mxArray
has more than two dimensions and you need to know exactly how many elements are in each dimension, then call mxGetSize
.
If array_ptr
points to a sparse mxArray
, mxGetN
still returns the number of columns, not the number of occupied columns.
Find the total number of elements in an mxArray
:
#include "mex.h" void mexFunction(int nlhs,mxArray *plhs[],int nrhs,const mxArray *prhs[]) { int rows, cols, total_elements; rows = mxGetM(prhs[0]); cols = mxGetN(prhs[0]); total_elements = rows * cols; printf("This matrix has %d elements.\n", total_elements); }For an additional example, see
mxGetN.c
in the mx
subdirectory of the examples
directory.
mxGetM
, mxGetNumberOfDimensions
, mxSetM
, mxSetN