mini.roots {mgcv} | R Documentation |

## Obtain square roots of penalty matrices

### Description

INTERNAL function to obtain square roots, `B[[i]]`

, of the penalty matrices `S[[i]]`

's having as few
columns as possible.

### Usage

```
mini.roots(S, off, np, rank = NULL)
```

### Arguments

`S` |
a list of penalty matrices, in packed form. |

`off` |
a vector where the i-th element is the offset for the i-th matrix.
The elements in columns |

`np` |
total number of parameters. |

`rank` |
here |

### Value

A list of matrix square roots such that `S[[i]]=B[[i]]%*%t(B[[i]])`

.

### Author(s)

Simon N. Wood <simon.wood@r-project.org>.

[Package

*mgcv*version 1.9-1 Index]