# Method trace

#### static member trace: Tensor<'T> -> Tensor<'T>

Calculates the trace of the matrix.

##### Declaration

`static member trace: a:Tensor<'T> -> Tensor<'T>`

##### Parameters

Type | Name | Description |
---|---|---|

Tensor<'T> | a | A square matrix. |

##### Returns

Type | Description |
---|---|

Tensor<'T> | The trace of the matrix. |

##### Remarks

The trace is is defined by the sum of the elements on the diagonal.

The matrix must be square.

If the specified tensor has more than two dimensions, the traces along the last two dimensions are returned as a tensor.

##### Examples

```
let a = HostTensor.zeros [3L; 3L]
let b = Tensor.trace a
```