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<?php |
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|
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/** |
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* |
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* Class for the creating "special" Matrices |
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* |
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* @copyright Copyright (c) 2018 Mark Baker (https://github.com/MarkBaker/PHPMatrix) |
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* @license https://opensource.org/licenses/MIT MIT |
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*/ |
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|
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namespace Matrix; |
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|
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/** |
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* Matrix Builder class. |
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* |
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* @package Matrix |
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*/ |
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class Builder |
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{ |
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/** |
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* Create a new matrix of specified dimensions, and filled with a specified value |
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* If the column argument isn't provided, then a square matrix will be created |
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* |
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* @param mixed $value |
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* @param int $rows |
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* @param int|null $columns |
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* @return Matrix |
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* @throws Exception |
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*/ |
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public static function createFilledMatrix($value, $rows, $columns = null) |
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{ |
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if ($columns === null) { |
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$columns = $rows; |
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} |
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|
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$rows = Matrix::validateRow($rows); |
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$columns = Matrix::validateColumn($columns); |
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|
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return new Matrix( |
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array_fill( |
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0, |
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$rows, |
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array_fill( |
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0, |
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$columns, |
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$value |
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) |
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) |
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); |
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} |
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|
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/** |
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* Create a new identity matrix of specified dimensions |
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* This will always be a square matrix, with the number of rows and columns matching the provided dimension |
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* |
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* @param int $dimensions |
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* @return Matrix |
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* @throws Exception |
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*/ |
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public static function createIdentityMatrix($dimensions) |
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{ |
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$grid = static::createFilledMatrix(null, $dimensions)->toArray(); |
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|
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for ($x = 0; $x < $dimensions; ++$x) { |
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$grid[$x][$x] = 1; |
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} |
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|
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return new Matrix($grid); |
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} |
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} |
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|
