| 1 |
<?php |
| 2 |
|
| 3 |
/** |
| 4 |
* |
| 5 |
* Function code for the matrix trace() function |
| 6 |
* |
| 7 |
* @copyright Copyright (c) 2018 Mark Baker (https://github.com/MarkBaker/PHPMatrix) |
| 8 |
* @license https://opensource.org/licenses/MIT MIT |
| 9 |
*/ |
| 10 |
|
| 11 |
namespace Matrix; |
| 12 |
|
| 13 |
/** |
| 14 |
* Returns the trace of a matrix or an array. |
| 15 |
* |
| 16 |
* @param Matrix|array $matrix Matrix or an array to treat as a matrix. |
| 17 |
* @return float The trace of the matrix |
| 18 |
* @throws Exception If argument isn't a valid matrix or array. |
| 19 |
*/ |
| 20 |
function trace($matrix) |
| 21 |
{ |
| 22 |
if (is_array($matrix)) { |
| 23 |
$matrix = new Matrix($matrix); |
| 24 |
} |
| 25 |
if (!$matrix instanceof Matrix) { |
| 26 |
throw new Exception('Must be Matrix or array'); |
| 27 |
} |
| 28 |
|
| 29 |
return Functions::trace($matrix); |
| 30 |
} |
| 31 |
|
