71 lines
1.7 KiB
PHP
71 lines
1.7 KiB
PHP
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<?php
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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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namespace Matrix;
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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 $fillValue
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* @param int $rows
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* @param int|null $columns
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* @return Matrix
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* @throws Exception
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*/
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public static function createFilledMatrix($fillValue, $rows, $columns = null)
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{
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if ($columns === null) {
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$columns = $rows;
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}
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$rows = Matrix::validateRow($rows);
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$columns = Matrix::validateColumn($columns);
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return new Matrix(
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array_fill(
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0,
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$rows,
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array_fill(
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0,
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$columns,
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$fillValue
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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, $fillValue = null)
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{
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$grid = static::createFilledMatrix($fillValue, $dimensions)->toArray();
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for ($x = 0; $x < $dimensions; ++$x) {
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$grid[$x][$x] = 1;
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}
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return new Matrix($grid);
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}
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}
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