Normalization of vectors.

normalize(v, w = NULL)

## Arguments

v |
vector |

w |
optional vector |

## Value

vnormalized `v`

wnormalized `w`

## Details

The vector `v`

is normalized to length 1. If `w`

is given, it is
normalized by the length of `v`

.

## Author

Nicole Kraemer, Mikio L. Braun

## Examples