NNZ Number of Nonzeros

Section: Sparse Matrix Support

Usage

Returns the number of nonzero elements in a matrix. The general format for its use is
   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

Example

--> 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