Number of columns in array
Call mxGetN to determine the number of columns in the specified mxArray.
If pm is an N-dimensional mxArray, mxGetN is the product of dimensions 2 through N. For example, if pm points to a four-dimensional mxArray having dimensions 13-by-5-by-4-by-6, mxGetN returns the value 120 (5 × 4 × 6). If the specified mxArray has more than two dimensions and you need to know exactly how many elements are in each dimension, call mxGetDimensions.
If pm points to a sparse mxArray, mxGetN still returns the number of columns, not the number of occupied columns.
Note: Fortran does not have an equivalent of size_t. mwPointer is a preprocessor macro that provides the appropriate Fortran type. The value returned by this function, however, is not a pointer.
See the following examples in matlabroot/extern/examples/refbook.
See the following examples in matlabroot/extern/examples/mx.
See the following examples in matlabroot/extern/examples/mex.
See the following examples in matlabroot/extern/examples/eng_mat.