Section: Sparse Matrix Support
y = nnz(x)
This function returns the number of nonzero elements in a matrix or array. This function works for both sparse and non-sparse arrays. For
--> a = [1,0,0,5;0,3,2,0] a = <int32> - size: [2 4] Columns 1 to 4 1 0 0 5 0 3 2 0 --> nnz(a) ans = <int32> - size: [1 1] 4 --> A = sparse(a) A = <int32> - size: [2 4] Matrix is sparse with 4 nonzeros --> nnz(A) ans = <int32> - size: [1 1] 4