Manipulate Multidimensional Numerical Arrays in C MEX Files
You can manipulate multidimensional numerical arrays by using typed data access
functions like mxGetDoubles
and
mxGetComplexDoubles
. The example findnz.c
takes an N-dimensional array of doubles and returns the indices for the nonzero elements
in the array.
Build the example.
mex -R2018a findnz.c
Create a sample matrix.
matrix = [ 3 0 9 0; 0 8 2 4; 0 9 2 4; 3 0 9 3; 9 9 2 0]
matrix = 3 0 9 0 0 8 2 4 0 9 2 4 3 0 9 3 9 9 2 0
findnz
determines the position of all nonzero elements in the
matrix.
nz = findnz(matrix)
nz = 1 1 4 1 5 1 2 2 3 2 5 2 1 3 2 3 3 3 4 3 5 3 2 4 3 4 4 4
See Also
mxGetDoubles
| mxGetComplexDoubles