MATLAB Function Reference |

Amount of storage allocated for nonzero matrix elements

**Syntax**

**Description**

```
n = nzmax(S)
```

returns the amount of storage allocated for nonzero elements.

If `S` is a sparse matrix... |
`nzmax(S)` is the number of storage locations allocated for the nonzero elements in `S` . |

If `S` is a full matrix... |
`nzmax(S) = prod(size(S))` . |

Often, `nnz(S)`

and `nzmax(S)`

are the same. But if `S`

is created by an operation which produces fill-in matrix elements, such as sparse matrix multiplication or sparse LU factorization, more storage may be allocated than is actually required, and `nzmax(S)`

reflects this. Alternatively, `sparse(i,j,s,m,n,nzmax)`

or its simpler form, `spalloc(m,n,nzmax)`

, can set `nzmax`

in anticipation of later fill-in.

**See Also**

`find`

, `isa`

, `nnz`

, `nonzeros`

, `size`

, `whos`

numel | ode45, ode23, ode113, ode15s, ode23s, ode23t, ode23tb |