# XMVectorSqrtEst function

Estimates the per-component square root of a vector.

## Syntax

```
XMVECTOR XM_CALLCONV XMVectorSqrtEst(
FXMVECTOR V
);
```

## Parameters

`V`

Vector whose square root is estimated.

## Return Value

Returns a vector. Each component is an estimate of the square-root of the corresponding component of *V*.

## Remarks

The square-root operation handles special input values as follows.

Input Value | Return Value |
---|---|

+Infinity | +Infinity |

+0.0f | +0.0f |

-0.0f | -0.0f |

< 0.0f | QNaN* |

- Note that due to implementation details, VMX128 returns -Infinity in this case instead of the standard QNaN.

`Est`

functions offer increased performance at the expense of reduced accuracy.
`Est`

functions are appropriate for non-critical calculations where accuracy can be sacrificed for speed.
The exact amount of lost accuracy and speed increase are platform dependent.

### Platform Requirements

Microsoft Visual Studio 2010 or Microsoft Visual Studio 2012 with the Windows SDK for Windows 8. Supported for Win32 desktop apps, Windows Store apps, and Windows Phone 8 apps.## Requirements

Target Platform |
Windows |

Header |
directxmath.h (include DirectXMath.h) |