R: Invert a symmetric positive-definite matrix

sinv {MESS} | R Documentation

## Invert a symmetric positive-definite matrix

### Description

Inverts a symmetric positive-definite matrix without requiring the Matrix package.

### Usage

    sinv(obj)

### Arguments

`obj` | The symmetric positive-definite matrix

### Details

This function does no error checking and it is up to the user to ensure that the input is indeed symmetric, positive-definite, and a matrix.

### Value

A matrix of the same size as the input object

### Author(s)

Claus Ekstrom, claus@rprimer.dk.

### Examples

    m <- matrix(c(1, 0, .5, .5, 0, 1, .5, .5, .5, .5, 1, .5, .5, .5, .5, 1), 4)
    sinv(m)

[Package MESS version 0.5.9 Index]