R: The trace of a matrix

matrix.trace {matrixcalc} | R Documentation

## The trace of a matrix

### Description

This function returns the trace of a given square numeric matrix.

### Usage

    matrix.trace(x)

### Arguments

`x` | a matrix

### Value

A numeric value which is the sum of the values on the diagonal.

### Note

If the argument x is not numeric, the function presents and error message and terminates. If the argument x is not a square matrix, the function presents an error message and terminates.

### Author(s)

Frederick Novomestky fnovomes@poly.edu

### References

Bellman, R. (1987). Matrix Analysis, Second edition, Classics in Applied Mathematics, Society for Industrial and Applied Mathematics.

### Examples

    A <- matrix( seq( 1, 16, 1 ), nrow=4, byrow=TRUE )
    matrix.trace( A )

[Package matrixcalc version 1.0-3 Index]