# Matrix.SetIdentity Method

## Definition

Changes this Matrix structure into an identity matrix.

```
public:
void SetIdentity();
```

`public void SetIdentity ();`

`member this.SetIdentity : unit -> unit`

`Public Sub SetIdentity ()`

## Examples

The following example shows how to turn a Matrix structure into an identity matrix.

```
private Matrix identityExample()
{
// Get the identity matrix, which is equal to
// (1,0,0,1,0,0).
Matrix myMatrix = Matrix.Identity;
Matrix m = new Matrix(1,0,0,1,0,0);
return myMatrix;
}
```

## Remarks

An identity matrix has a value of 1 in coefficients [1,1],[2,2],[3,3] and a value of 0 in the rest of the coefficients. This correlates to setting M11 and M22 to 1 and M12, M21, OffsetX, and OffsetY to 0. In an affine matrix, which is the implementation that Windows Presentation Foundation (WPF) uses for the Matrix structure, coefficients [3,1],[3,2],[3.3] are implied to always have the values 0,0,1 respectively.

1 | 0 | 0 |

0 | 1 | 0 |

0 | 0 | 1 |

For an identity matrix, the ToString method returns the string "Identity", instead of the coefficients of the Matrix.