# nonzeros

Nonzero matrix elements

## Syntax

``v = nonzeros(A)``

## Description

example

````v = nonzeros(A)` returns a full column vector of the nonzero elements in `A`. The elements in `v` are ordered by columns.```

## Examples

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Use `nonzeros` to return the nonzero elements in a sparse matrix.

Create a 10-by-10 sparse matrix that contains a few nonzero elements. The typical display of sparse matrices shows a list of the nonzero values and their locations.

`A = sparse([1 3 2 1],[1 1 2 3],1:4,10,10)`
```A = (1,1) 1 (3,1) 2 (2,2) 3 (1,3) 4 ```

Find the values of the nonzero elements.

`v = nonzeros(A)`
```v = 4×1 1 2 3 4 ```

Use `nonzeros`, `nnz`, and `find` to locate and count nonzero matrix elements.

Create a 10-by-10 random sparse matrix with 7% density of nonzeros.

`A = sprand(10,10,0.07);`

Use `nonzeros` to find the values of the nonzero elements.

`v = nonzeros(A)`
```v = 7×1 0.9595 0.4218 0.7922 0.8003 0.1419 0.9157 0.6557 ```

Use `nnz` to count the number of nonzeros.

`n = nnz(A)`
```n = 7 ```

Use `find` to get the indices and values of the nonzeros.

`[i,j,v] = find(A)`
```i = 7×1 10 3 9 1 2 7 10 ```
```j = 7×1 2 5 6 10 10 10 10 ```
```v = 7×1 0.9595 0.4218 0.7922 0.8003 0.1419 0.9157 0.6557 ```

## Input Arguments

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Input array, specified as a vector, matrix, or multidimensional array. `A` can be full or sparse.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64` | `logical` | `char`
Complex Number Support: Yes

## Output Arguments

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Nonzero elements, returned as a column vector. `v` is returned in full-storage regardless of whether `A` is full or sparse. The elements in `v` are ordered first by column subscript and then by row subscript.

`nonzeros` gives the `v`, but not the indices `i` and `j`, from ```[i,j,v] = find(A)```. Generally,

`length(v) = nnz(A) <= nzmax(A) <= prod(size(A))`