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1178 lines
36 KiB
1178 lines
36 KiB
<?php
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/**
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* EvalMath - Safely evaluate math expressions.
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*
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* Based on EvalMath by Miles Kaufmann, with modifications by Petr Skoda.
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*
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* @link https://github.com/moodle/moodle/blob/master/lib/evalmath/evalmath.class.php
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*
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* @package TablePress
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* @subpackage Formulas
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* @author Miles Kaufmann, Petr Skoda, Tobias Bäthge
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* @since 1.0.0
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*/
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// Prohibit direct script loading.
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defined( 'ABSPATH' ) || die( 'No direct script access allowed!' );
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/**
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* Class to safely evaluate math expressions.
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*
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* @package TablePress
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* @subpackage Formulas
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* @since 1.0.0
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*/
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class EvalMath {
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/**
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* Pattern used for a valid function or variable name.
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*
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* Note, variable and function names are case insensitive.
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*
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* @since 1.0.0
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* @var string
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*/
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protected static $name_pattern = '[a-z][a-z0-9_]*';
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/**
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* Whether to suppress errors and warnings.
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*
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* @since 1.0.0
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* @var bool
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*/
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public $suppress_errors = false;
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/**
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* The last error message that was raised.
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*
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* @since 1.0.0
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* @var string
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*/
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public $last_error = '';
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/**
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* Variables (including constants).
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*
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* @since 1.0.0
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* @var array<string, mixed>
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*/
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public $variables = array();
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/**
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* User-defined functions.
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*
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* @since 1.0.0
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* @var array<string, mixed>
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*/
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protected $functions = array();
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/**
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* Constants.
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*
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* @since 1.0.0
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* @var array<string, mixed>
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*/
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protected $constants = array();
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/**
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* Built-in functions.
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*
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* @since 1.0.0
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* @var string[]
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*/
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protected $builtin_functions = array(
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'sin',
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'sinh',
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'arcsin',
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'asin',
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'arcsinh',
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'asinh',
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'cos',
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'cosh',
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'arccos',
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'acos',
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'arccosh',
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'acosh',
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'tan',
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'tanh',
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'arctan',
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'atan',
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'arctanh',
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'atanh',
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'sqrt',
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'abs',
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'ln',
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'log10',
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'exp',
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'floor',
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'ceil',
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);
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/**
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* Emulated functions.
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*
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* @since 1.0.0
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* @var array<string, int[]>
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*/
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protected $calc_functions = array(
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'average' => array( -1 ),
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'mean' => array( -1 ),
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'median' => array( -1 ),
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'mode' => array( -1 ),
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'range' => array( -1 ),
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'max' => array( -1 ),
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'min' => array( -1 ),
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'mod' => array( 2 ),
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'pi' => array( 0 ),
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'power' => array( 2 ),
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'log' => array( 1, 2 ),
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'round' => array( 1, 2 ),
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'number_format' => array( 1, 2 ),
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'number_format_eu' => array( 1, 2 ),
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'sum' => array( -1 ),
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'counta' => array( -1 ),
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'product' => array( -1 ),
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'rand_int' => array( 2 ),
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'rand_float' => array( 0 ),
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'arctan2' => array( 2 ),
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'atan2' => array( 2 ),
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'if' => array( 3 ),
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'not' => array( 1 ),
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'and' => array( -1 ),
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'or' => array( -1 ),
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);
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/**
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* Class constructor.
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*
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* @since 1.0.0
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*/
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public function __construct() {
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// Set default constants.
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$this->variables['pi'] = pi();
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$this->variables['e'] = exp( 1 );
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}
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/**
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* Evaluate a math expression without checking it for variable or function assignments.
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*
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* @since 1.0.0
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*
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* @param string $expression The expression that shall be evaluated.
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* @return string|false Evaluated expression or false on error.
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*/
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public function evaluate( $expression ) /* : string|false */ {
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return $this->pfx( $this->nfx( $expression ) );
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}
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/**
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* Evaluate a math expression or formula, and check it for variable and function assignments.
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*
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* @since 1.0.0
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*
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* @param string $expression The expression that shall be evaluated.
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* @return string|bool Evaluated expression, true on successful function assignment, or false on error.
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*/
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public function assign_and_evaluate( $expression ) /* : string|bool */ {
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$this->last_error = '';
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$expression = trim( $expression );
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$expression = rtrim( $expression, ';' );
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// Is the expression a variable assignment?
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if ( 1 === preg_match( '/^\s*(' . self::$name_pattern . ')\s*=\s*(.+)$/', $expression, $matches ) ) {
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// Make sure we're not assigning to a constant.
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if ( in_array( $matches[1], $this->constants, true ) ) {
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return $this->raise_error( 'cannot_assign_to_constant', $matches[1] );
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}
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// Evaluate the assignment.
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$tmp = $this->pfx( $this->nfx( $matches[2] ) );
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if ( false === $tmp ) {
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return false;
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}
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// If it could be evaluated, add it to the variable array, ...
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$this->variables[ $matches[1] ] = $tmp;
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// ... and return the resulting value.
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return $tmp;
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// Is the expression a function assignment?
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} elseif ( 1 === preg_match( '/^\s*(' . self::$name_pattern . ')\s*\(\s*(' . self::$name_pattern . '(?:\s*,\s*' . self::$name_pattern . ')*)\s*\)\s*=\s*(.+)$/', $expression, $matches ) ) {
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// Get the function name.
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$function_name = $matches[1];
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// Make sure it isn't a built-in function -- we can't redefine those.
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if ( in_array( $matches[1], $this->builtin_functions, true ) ) {
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return $this->raise_error( 'cannot_redefine_builtin_function', $matches[1] );
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}
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// Get the function arguments after removing all whitespace.
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$matches[2] = str_replace( array( "\n", "\r", "\t", ' ' ), '', $matches[2] );
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$args = explode( ',', $matches[2] );
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// Convert the function definition to postfix notation.
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$stack = $this->nfx( $matches[3] );
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if ( false === $stack ) {
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return false;
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}
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// Freeze the state of the non-argument variables.
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$stack_count = count( $stack );
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for ( $i = 0; $i < $stack_count; $i++ ) {
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$token = $stack[ $i ];
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if ( 1 === preg_match( '/^' . self::$name_pattern . '$/', $token ) && ! in_array( $token, $args, true ) ) {
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if ( array_key_exists( $token, $this->variables ) ) {
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$stack[ $i ] = $this->variables[ $token ];
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} else {
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return $this->raise_error( 'undefined_variable_in_function_definition', $token );
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}
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}
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}
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$this->functions[ $function_name ] = array( 'args' => $args, 'func' => $stack );
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return true;
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// No variable or function assignment, so straight-up evaluation.
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} else {
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return $this->evaluate( $expression );
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}
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}
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/**
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* Return all user-defined variables and values.
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*
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* @since 1.0.0
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*
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* @return array<string, mixed> User-defined variables and values.
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*/
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public function variables(): array {
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return $this->variables;
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}
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/**
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* Return all user-defined functions with their arguments.
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*
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* @since 1.0.0
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*
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* @return array<int, string> User-defined functions.
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*/
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public function functions(): array {
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$output = array();
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foreach ( $this->functions as $name => $data ) {
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$output[] = $name . '( ' . implode( ', ', $data['args'] ) . ' )';
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}
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return $output;
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}
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/*
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* Internal methods.
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*/
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/**
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* Convert infix to postfix notation.
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*
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* @since 1.0.0
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*
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* @param string $expression Math expression that shall be converted.
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* @return mixed[]|false Converted expression or false on error.
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*/
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protected function nfx( $expression ) /* : mixed[]|false */ {
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$index = 0;
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$stack = new EvalMath_Stack();
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$output = array(); // postfix form of expression, to be passed to pfx().
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$expression = trim( strtolower( $expression ) );
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$ops = array( '+', '-', '*', '/', '^', '_', '>', '<', '=', '%' );
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$ops_r = array( '+' => 0, '-' => 0, '*' => 0, '/' => 0, '^' => 1, '>' => 0, '<' => 0, '=' => 0, '%' => 0 ); // Right-associative operator?
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$ops_p = array( '+' => 0, '-' => 0, '*' => 1, '/' => 1, '_' => 1, '^' => 2, '>' => 0, '<' => 0, '=' => 0, '%' => 1 ); // Operator precedence.
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// We use this in syntax-checking the expression and determining when a - (minus) is a negation.
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$expecting_operator = false;
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// Make sure the characters are all good.
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if ( 1 === preg_match( '/[^\%\w\s+*^\/()\.,-<>=]/', $expression, $matches ) ) {
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return $this->raise_error( 'illegal_character_general', $matches[0] );
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}
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// Infinite Loop for the conversion.
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while ( true ) {
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// Get the first character at the current index.
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$op = substr( $expression, $index, 1 );
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// Find out if we're currently at the beginning of a number/variable/function/parenthesis/operand.
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$ex = preg_match( '/^(' . self::$name_pattern . '\(?|\d+(?:\.\d*)?(?:(e[+-]?)\d*)?|\.\d+|\()/', substr( $expression, $index ), $match );
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// Is it a negation instead of a minus (in a subtraction)?
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if ( '-' === $op && ! $expecting_operator ) {
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// Put a negation on the stack.
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$stack->push( '_' );
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++$index;
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} elseif ( '_' === $op ) {
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// We have to explicitly deny underscores (as they mean negation), because they are legal on the stack.
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return $this->raise_error( 'illegal_character_underscore' );
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// Are we putting an operator on the stack?
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} elseif ( ( in_array( $op, $ops, true ) || $ex ) && $expecting_operator ) {
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// Are we expecting an operator but have a number/variable/function/opening parethesis?
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if ( $ex ) {
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// It's an implicit multiplication.
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$op = '*';
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--$index;
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}
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// Heart of the algorithm: .
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// phpcs:ignore Generic.CodeAnalysis.AssignmentInCondition.FoundInWhileCondition
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while ( $stack->count > 0 && ( $o2 = $stack->last() ) && in_array( $o2, $ops, true ) && ( $ops_r[ $op ] ? $ops_p[ $op ] < $ops_p[ $o2 ] : $ops_p[ $op ] <= $ops_p[ $o2 ] ) ) {
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// Pop stuff off the stack into the output.
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$output[] = $stack->pop();
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}
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// Many thanks: https://en.wikipedia.org/wiki/Reverse_Polish_notation .
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$stack->push( $op ); // Finally put OUR operator onto the stack.
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++$index;
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$expecting_operator = false;
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// Ready to close a parenthesis?
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} elseif ( ')' === $op && $expecting_operator ) {
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// Pop off the stack back to the last (.
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// phpcs:ignore Generic.CodeAnalysis.AssignmentInCondition.FoundInWhileCondition
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while ( '(' !== ( $o2 = $stack->pop() ) ) {
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if ( is_null( $o2 ) ) {
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return $this->raise_error( 'unexpected_closing_bracket' );
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} else {
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$output[] = $o2;
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}
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}
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// Did we just close a function?
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if ( 1 === preg_match( '/^(' . self::$name_pattern . ')\($/', (string) $stack->last( 2 ), $matches ) ) {
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// Get the function name.
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$function_name = $matches[1];
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// See how many arguments there were (cleverly stored on the stack, thank you).
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$arg_count = $stack->pop();
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$stack->pop(); // $fn
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// Send function to output.
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$output[] = array( 'function_name' => $function_name, 'arg_count' => $arg_count );
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// Check the argument count, depending on what type of function we have.
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if ( in_array( $function_name, $this->builtin_functions, true ) ) {
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// Built-in functions.
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if ( $arg_count > 1 ) { // @phpstan-ignore-line
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$error_data = array( 'expected' => 1, 'given' => $arg_count );
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return $this->raise_error( 'wrong_number_of_arguments', $error_data );
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}
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} elseif ( array_key_exists( $function_name, $this->calc_functions ) ) {
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// Calc-emulation functions.
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$counts = $this->calc_functions[ $function_name ];
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// @phpstan-ignore-next-line
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if ( in_array( -1, $counts, true ) && $arg_count > 0 ) { // phpcs:ignore Generic.CodeAnalysis.EmptyStatement.DetectedIf
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// Everything is fine, we expected an indefinite number arguments and got some.
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} elseif ( ! in_array( $arg_count, $counts, true ) ) { // @phpstan-ignore-line
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$error_data = array( 'expected' => implode( '/', $this->calc_functions[ $function_name ] ), 'given' => $arg_count );
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return $this->raise_error( 'wrong_number_of_arguments', $error_data );
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}
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} elseif ( array_key_exists( $function_name, $this->functions ) ) {
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// User-defined functions.
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if ( count( $this->functions[ $function_name ]['args'] ) !== $arg_count ) {
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$error_data = array( 'expected' => count( $this->functions[ $function_name ]['args'] ), 'given' => $arg_count );
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return $this->raise_error( 'wrong_number_of_arguments', $error_data );
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}
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} else {
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// Did we somehow push a non-function on the stack? This should never happen.
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return $this->raise_error( 'internal_error' );
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}
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}
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++$index;
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// Did we just finish a function argument?
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} elseif ( ',' === $op && $expecting_operator ) {
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// phpcs:ignore Generic.CodeAnalysis.AssignmentInCondition.FoundInWhileCondition
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while ( '(' !== ( $o2 = $stack->pop() ) ) {
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if ( is_null( $o2 ) ) {
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// Oops, never had a (.
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return $this->raise_error( 'unexpected_comma' );
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} else {
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// Pop the argument expression stuff and push onto the output.
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$output[] = $o2;
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}
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}
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// Make sure there was a function.
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if ( 0 === preg_match( '/^(' . self::$name_pattern . ')\($/', (string) $stack->last( 2 ), $matches ) ) {
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return $this->raise_error( 'unexpected_comma' );
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}
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// Increment the argument count.
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$stack->push( $stack->pop() + 1 ); // @phpstan-ignore-line
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// Put the ( back on, we'll need to pop back to it again.
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$stack->push( '(' );
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++$index;
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$expecting_operator = false;
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} elseif ( '(' === $op && ! $expecting_operator ) {
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$stack->push( '(' ); // That was easy.
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++$index;
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// Do we now have a function/variable/number?
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} elseif ( $ex && ! $expecting_operator ) {
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$expecting_operator = true;
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$value = $match[1];
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// May be a function, or variable with implicit multiplication against parentheses...
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if ( 1 === preg_match( '/^(' . self::$name_pattern . ')\($/', $value, $matches ) ) {
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// Is it a function?
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if ( in_array( $matches[1], $this->builtin_functions, true ) || array_key_exists( $matches[1], $this->functions ) || array_key_exists( $matches[1], $this->calc_functions ) ) {
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$stack->push( $value );
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$stack->push( 1 );
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$stack->push( '(' );
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$expecting_operator = false;
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// It's a variable with implicit multiplication.
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} else {
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$value = $matches[1];
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$output[] = $value;
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}
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} else {
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// It's a plain old variable or number.
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$output[] = $value;
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}
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$index += strlen( $value );
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} elseif ( ')' === $op ) {
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// It could be only custom function with no arguments or a general error.
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if ( '(' !== $stack->last() || 1 !== $stack->last( 2 ) ) {
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return $this->raise_error( 'unexpected_closing_bracket' );
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}
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// Did we just close a function?
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if ( 1 === preg_match( '/^(' . self::$name_pattern . ')\($/', (string) $stack->last( 3 ), $matches ) ) {
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$stack->pop(); // (
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$stack->pop(); // 1
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$stack->pop(); // $fn
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// Get the function name.
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$function_name = $matches[1];
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if ( isset( $this->calc_functions[ $function_name ] ) ) {
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// Custom calc-emulation function.
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$counts = $this->calc_functions[ $function_name ];
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} else {
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// Default count for built-in functions.
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$counts = array( 1 );
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}
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if ( ! in_array( 0, $counts, true ) ) {
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$error_data = array( 'expected' => $counts, 'given' => 0 );
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return $this->raise_error( 'wrong_number_of_arguments', $error_data );
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}
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// Send function to output.
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$output[] = array( 'function_name' => $function_name, 'arg_count' => 0 );
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++$index;
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$expecting_operator = true;
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} else {
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return $this->raise_error( 'unexpected_closing_bracket' );
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}
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|
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// Miscellaneous error checking.
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} elseif ( in_array( $op, $ops, true ) && ! $expecting_operator ) {
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return $this->raise_error( 'unexpected_operator', $op );
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|
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// I don't even want to know what you did to get here.
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} else {
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return $this->raise_error( 'an_unexpected_error_occurred' );
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}
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if ( strlen( $expression ) === $index ) {
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// Did we end with an operator? Bad.
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if ( in_array( $op, $ops, true ) ) {
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return $this->raise_error( 'operator_lacks_operand', $op );
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} else {
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break;
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|
}
|
|
}
|
|
|
|
// Step the index past whitespace (pretty much turns whitespace into implicit multiplication if no operator is there).
|
|
while ( ' ' === substr( $expression, $index, 1 ) ) {
|
|
++$index;
|
|
}
|
|
} // while ( true )
|
|
|
|
// Pop everything off the stack and push onto output.
|
|
// phpcs:ignore Generic.CodeAnalysis.AssignmentInCondition.FoundInWhileCondition
|
|
while ( ! is_null( $op = $stack->pop() ) ) { // @phpstan-ignore-line
|
|
if ( '(' === $op ) {
|
|
// If there are (s on the stack, ()s were unbalanced.
|
|
return $this->raise_error( 'expecting_a_closing_bracket' );
|
|
}
|
|
$output[] = $op;
|
|
}
|
|
|
|
return $output;
|
|
}
|
|
|
|
/**
|
|
* Evaluate postfix notation.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param array<int, string|mixed[]>|false $tokens [description].
|
|
* @param array<string, mixed> $variables Optional. [description].
|
|
* @return mixed [description].
|
|
*/
|
|
protected function pfx( $tokens, array $variables = array() ) /* : mixed */ {
|
|
if ( false === $tokens ) {
|
|
return false;
|
|
}
|
|
|
|
$stack = new EvalMath_Stack();
|
|
|
|
foreach ( $tokens as $token ) {
|
|
// If the token is a function, pop arguments off the stack, hand them to the function, and push the result back on.
|
|
if ( is_array( $token ) ) { // it's a function!
|
|
$function_name = $token['function_name'];
|
|
$count = $token['arg_count'];
|
|
|
|
if ( in_array( $function_name, $this->builtin_functions, true ) ) {
|
|
// Built-in function.
|
|
|
|
$op1 = $stack->pop();
|
|
if ( is_null( $op1 ) ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
}
|
|
// For the "arc" trigonometric synonyms.
|
|
$function_name = preg_replace( '/^arc/', 'a', $function_name );
|
|
// Rewrite "ln" (only allows one argument) to "log" (natural logarithm).
|
|
if ( 'ln' === $function_name ) {
|
|
$function_name = 'log';
|
|
}
|
|
// Perfectly safe eval().
|
|
// phpcs:ignore Squiz.PHP.Eval.Discouraged
|
|
eval( '$stack->push( ' . $function_name . '( $op1 ) );' );
|
|
} elseif ( array_key_exists( $function_name, $this->calc_functions ) ) {
|
|
// Calc-emulation function.
|
|
|
|
// Get function arguments.
|
|
$args = array();
|
|
for ( $i = $count - 1; $i >= 0; $i-- ) {
|
|
$arg = $stack->pop();
|
|
if ( is_null( $arg ) ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
} else {
|
|
$args[] = $arg;
|
|
}
|
|
}
|
|
// Rewrite some functions to their synonyms.
|
|
if ( 'if' === $function_name ) {
|
|
$function_name = 'func_if';
|
|
} elseif ( 'not' === $function_name ) {
|
|
$function_name = 'func_not';
|
|
} elseif ( 'and' === $function_name ) {
|
|
$function_name = 'func_and';
|
|
} elseif ( 'or' === $function_name ) {
|
|
$function_name = 'func_or';
|
|
} elseif ( 'mean' === $function_name ) {
|
|
$function_name = 'average';
|
|
} elseif ( 'arctan2' === $function_name ) {
|
|
$function_name = 'atan2';
|
|
}
|
|
$result = EvalMath_Functions::$function_name( ...array_reverse( $args ) );
|
|
if ( false === $result ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
}
|
|
$stack->push( $result );
|
|
} elseif ( array_key_exists( $function_name, $this->functions ) ) {
|
|
// User-defined function.
|
|
|
|
// Get function arguments.
|
|
$args = array();
|
|
for ( $i = count( $this->functions[ $function_name ]['args'] ) - 1; $i >= 0; $i-- ) {
|
|
$arg = $stack->pop();
|
|
if ( is_null( $arg ) ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
} else {
|
|
$args[ $this->functions[ $function_name ]['args'][ $i ] ] = $arg;
|
|
}
|
|
}
|
|
// yay... recursion!
|
|
$stack->push( $this->pfx( $this->functions[ $function_name ]['func'], $args ) ); // @phpstan-ignore-line
|
|
}
|
|
} elseif ( in_array( $token, array( '+', '-', '*', '/', '^', '>', '<', '=', '%' ), true ) ) {
|
|
// If the token is a binary operator, pop two values off the stack, do the operation, and push the result back on.
|
|
$op2 = $stack->pop();
|
|
if ( is_null( $op2 ) ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
}
|
|
$op1 = $stack->pop();
|
|
if ( is_null( $op1 ) ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
}
|
|
switch ( $token ) {
|
|
case '+':
|
|
$stack->push( $op1 + $op2 );
|
|
break;
|
|
case '-':
|
|
$stack->push( $op1 - $op2 );
|
|
break;
|
|
case '*':
|
|
$stack->push( $op1 * $op2 );
|
|
break;
|
|
case '/':
|
|
if ( 0 === $op2 || '0' === $op2 ) {
|
|
return $this->raise_error( 'division_by_zero' );
|
|
}
|
|
$stack->push( $op1 / $op2 );
|
|
break;
|
|
case '^':
|
|
$stack->push( pow( $op1, $op2 ) );
|
|
break;
|
|
case '>':
|
|
$stack->push( (int) ( $op1 > $op2 ) );
|
|
break;
|
|
case '<':
|
|
$stack->push( (int) ( $op1 < $op2 ) );
|
|
break;
|
|
case '=':
|
|
// phpcs:ignore WordPress.PHP.StrictComparisons.LooseComparison,Universal.Operators.StrictComparisons.LooseEqual
|
|
$stack->push( (int) ( $op1 == $op2 ) ); // Don't use === as the variable type can differ (int/double/bool).
|
|
break;
|
|
case '%':
|
|
$stack->push( $op1 % $op2 );
|
|
break;
|
|
}
|
|
} elseif ( '_' === $token ) {
|
|
// If the token is a unary operator, pop one value off the stack, do the operation, and push it back on.
|
|
$stack->push( -1 * $stack->pop() );
|
|
} elseif ( is_numeric( $token ) ) {
|
|
// If the token is a number, push it on the stack.
|
|
$stack->push( $token );
|
|
} elseif ( array_key_exists( $token, $this->variables ) ) {
|
|
// If the token is a variable, push it on the stack.
|
|
$stack->push( $this->variables[ $token ] );
|
|
} elseif ( array_key_exists( $token, $variables ) ) {
|
|
// If the token is a variable, push it on the stack.
|
|
$stack->push( $variables[ $token ] );
|
|
} else {
|
|
return $this->raise_error( 'undefined_variable', $token );
|
|
}
|
|
}
|
|
// When we're out of tokens, the stack should have a single element, the final result.
|
|
if ( 1 !== $stack->count ) {
|
|
return $this->raise_error( 'internal_error' );
|
|
}
|
|
return $stack->pop();
|
|
}
|
|
|
|
/**
|
|
* Raise an error.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param string $message Error message.
|
|
* @param mixed[]|string $error_data Optional. Additional error data.
|
|
* @return false False, to stop evaluation.
|
|
*/
|
|
protected function raise_error( $message, $error_data = null ): bool {
|
|
$this->last_error = $this->get_error_string( $message, $error_data );
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Get a translated string for an error message.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @link https://github.com/moodle/moodle/blob/13264f35057d2f37374ec3e0e8ad4070f4676bd7/lang/en/mathslib.php
|
|
* @link https://github.com/moodle/moodle/blob/8e54ce9717c19f768b95f4332f70e3180ffafc46/lib/moodlelib.php#L6323
|
|
*
|
|
* @param string $identifier Identifier of the string.
|
|
* @param mixed[]|string $error_data Optional. Additional error data.
|
|
* @return string Translated string.
|
|
*/
|
|
protected function get_error_string( $identifier, $error_data = null ): string {
|
|
$strings = array();
|
|
$strings['an_unexpected_error_occurred'] = 'an unexpected error occurred';
|
|
$strings['cannot_assign_to_constant'] = 'cannot assign to constant \'{$error_data}\'';
|
|
$strings['cannot_redefine_builtin_function'] = 'cannot redefine built-in function \'{$error_data}()\'';
|
|
$strings['division_by_zero'] = 'division by zero';
|
|
$strings['expecting_a_closing_bracket'] = 'expecting a closing bracket';
|
|
$strings['illegal_character_general'] = 'illegal character \'{$error_data}\'';
|
|
$strings['illegal_character_underscore'] = 'illegal character \'_\'';
|
|
$strings['internal_error'] = 'internal error';
|
|
$strings['operator_lacks_operand'] = 'operator \'{$error_data}\' lacks operand';
|
|
$strings['undefined_variable'] = 'undefined variable \'{$error_data}\'';
|
|
$strings['undefined_variable_in_function_definition'] = 'undefined variable \'{$error_data}\' in function definition';
|
|
$strings['unexpected_closing_bracket'] = 'unexpected closing bracket';
|
|
$strings['unexpected_comma'] = 'unexpected comma';
|
|
$strings['unexpected_operator'] = 'unexpected operator \'{$error_data}\'';
|
|
$strings['wrong_number_of_arguments'] = 'wrong number of arguments ({$error_data->given} given, {$error_data->expected} expected)';
|
|
|
|
$a_string = $strings[ $identifier ];
|
|
|
|
if ( null !== $error_data ) {
|
|
if ( is_array( $error_data ) ) {
|
|
$search = array();
|
|
$replace = array();
|
|
foreach ( $error_data as $key => $value ) {
|
|
if ( is_int( $key ) ) {
|
|
// We do not support numeric keys!
|
|
continue;
|
|
}
|
|
if ( is_object( $value ) || is_array( $value ) ) {
|
|
$value = (array) $value;
|
|
if ( count( $value ) > 1 ) {
|
|
$value = implode( ' or ', $value );
|
|
} else {
|
|
$value = (string) $value[0];
|
|
if ( '-1' === $value ) {
|
|
$value = 'at least 1';
|
|
}
|
|
}
|
|
}
|
|
$search[] = '{$error_data->' . $key . '}';
|
|
$replace[] = (string) $value;
|
|
}
|
|
if ( $search ) {
|
|
$a_string = str_replace( $search, $replace, $a_string );
|
|
}
|
|
} else {
|
|
$a_string = str_replace( '{$error_data}', (string) $error_data, $a_string );
|
|
}
|
|
}
|
|
|
|
return $a_string;
|
|
}
|
|
|
|
} // class EvalMath
|
|
|
|
/**
|
|
* Stack for the postfix/infix conversion of math expressions.
|
|
*
|
|
* @package TablePress
|
|
* @subpackage Formulas
|
|
* @since 1.0.0
|
|
*/
|
|
class EvalMath_Stack { // phpcs:ignore Generic.Files.OneObjectStructurePerFile.MultipleFound,Generic.Classes.OpeningBraceSameLine.ContentAfterBrace
|
|
|
|
/**
|
|
* The stack.
|
|
*
|
|
* @since 1.0.0
|
|
* @var mixed[]
|
|
*/
|
|
protected $stack = array();
|
|
|
|
/**
|
|
* Number of items on the stack.
|
|
*
|
|
* @since 1.0.0
|
|
* @var int
|
|
*/
|
|
public $count = 0;
|
|
|
|
/**
|
|
* Push an item onto the stack.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param mixed $value The item that is pushed onto the stack.
|
|
*/
|
|
public function push( $value ): void {
|
|
$this->stack[ $this->count ] = $value;
|
|
++$this->count;
|
|
}
|
|
|
|
/**
|
|
* Pop an item from the top of the stack.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @return mixed|null The item that is popped from the stack.
|
|
*/
|
|
public function pop() /* : mixed|null */ {
|
|
if ( $this->count > 0 ) {
|
|
--$this->count;
|
|
return $this->stack[ $this->count ];
|
|
}
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* Pop an item from the end of the stack.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param int $n Count from the end of the stack.
|
|
* @return mixed|null The item that is popped from the stack.
|
|
*/
|
|
public function last( $n = 1 ) /* : mixed|null */ {
|
|
if ( ( $this->count - $n ) >= 0 ) {
|
|
return $this->stack[ $this->count - $n ];
|
|
}
|
|
return null;
|
|
}
|
|
|
|
} // class EvalMath_Stack
|
|
|
|
/**
|
|
* Common math functions, prepared for usage in EvalMath.
|
|
*
|
|
* @package TablePress
|
|
* @subpackage EvalMath
|
|
* @since 1.0.0
|
|
*/
|
|
class EvalMath_Functions { // phpcs:ignore Generic.Files.OneObjectStructurePerFile.MultipleFound,Generic.Classes.OpeningBraceSameLine.ContentAfterBrace
|
|
|
|
/**
|
|
* Seed for the generation of random numbers.
|
|
*
|
|
* @since 1.0.0
|
|
* @var string|null
|
|
*/
|
|
protected static $random_seed = null;
|
|
|
|
/**
|
|
* Choose from two values based on an if-condition.
|
|
*
|
|
* "if" is not a valid function name, which is why it's prefixed with "func_".
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $condition Condition.
|
|
* @param double|int $statement Return value if the condition is true.
|
|
* @param double|int $alternative Return value if the condition is false.
|
|
* @return double|int Result of the if check.
|
|
*/
|
|
public static function func_if( $condition, $statement, $alternative ) /* : float|int */ {
|
|
return ( (bool) $condition ? $statement : $alternative );
|
|
}
|
|
|
|
/**
|
|
* Return the negation (boolean "not") of a value.
|
|
*
|
|
* Similar to "func_if", the function name is prefixed with "func_", although it wouldn't be necessary.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $value Value to be negated.
|
|
* @return int Negated value (0 for false, 1 for true).
|
|
*/
|
|
public static function func_not( $value ): int {
|
|
return (int) ! (bool) $value;
|
|
}
|
|
|
|
/**
|
|
* Calculate the conjunction (boolean "and") of some values.
|
|
*
|
|
* "and" is not a valid function name, which is why it's prefixed with "func_".
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the conjunction shall be calculated.
|
|
* @return int Conjunction of the passed arguments.
|
|
*/
|
|
public static function func_and( ...$args ): int {
|
|
foreach ( $args as $value ) {
|
|
if ( ! $value ) {
|
|
return 0;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* Calculate the disjunction (boolean "or") of some values.
|
|
*
|
|
* "or" is not a valid function name, which is why it's prefixed with "func_".
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the disjunction shall be calculated.
|
|
* @return int Disjunction of the passed arguments.
|
|
*/
|
|
public static function func_or( ...$args ): int {
|
|
foreach ( $args as $value ) {
|
|
if ( $value ) {
|
|
return 1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Return the (rounded) value of Pi.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @return double Rounded value of Pi.
|
|
*/
|
|
public static function pi(): float {
|
|
return pi();
|
|
}
|
|
|
|
/**
|
|
* Calculate the sum of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the sum shall be calculated.
|
|
* @return double|int Sum of the passed arguments.
|
|
*/
|
|
public static function sum( ...$args ) /* : float|int */ {
|
|
return array_sum( $args );
|
|
}
|
|
|
|
/**
|
|
* Count the number of non-empty arguments.
|
|
*
|
|
* @since 1.10.0
|
|
*
|
|
* @param double|int ...$args Values for which the number of non-empty elements shall be counted.
|
|
* @return int Counted number of non-empty elements in the passed values.
|
|
*/
|
|
public static function counta( ...$args ): int {
|
|
return count( array_filter( $args ) );
|
|
}
|
|
|
|
/**
|
|
* Calculate the product of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the product shall be calculated.
|
|
* @return double|int Product of the passed arguments.
|
|
*/
|
|
public static function product( ...$args ) /* : float|int */ {
|
|
return array_product( $args );
|
|
}
|
|
|
|
/**
|
|
* Calculate the average/mean value of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the average shall be calculated.
|
|
* @return double|int Average value of the passed arguments.
|
|
*/
|
|
public static function average( ...$args ) /* : float|int */ {
|
|
// Catch division by zero.
|
|
if ( 0 === count( $args ) ) {
|
|
return 0;
|
|
}
|
|
return array_sum( $args ) / count( $args );
|
|
}
|
|
|
|
/**
|
|
* Calculate the median of the arguments.
|
|
*
|
|
* For even counts of arguments, the upper median is returned.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param array<int, double|int> ...$args Values for which the median shall be calculated.
|
|
* @return double|int Median of the passed arguments.
|
|
*/
|
|
public static function median( array ...$args ) /* : float|int */ {
|
|
sort( $args );
|
|
$middle = intdiv( count( $args ), 2 ); // Upper median for even counts.
|
|
return $args[ $middle ]; // @phpstan-ignore-line
|
|
}
|
|
|
|
/**
|
|
* Calculate the mode of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param array<int, double|int> ...$args Values for which the mode shall be calculated.
|
|
* @return double|int Mode of the passed arguments.
|
|
*/
|
|
public static function mode( ...$args ) /* : float|int */ {
|
|
$values = array_count_values( $args );
|
|
asort( $values );
|
|
return array_key_last( $values ); // @phpstan-ignore-line
|
|
}
|
|
|
|
/**
|
|
* Calculate the range of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the range shall be calculated.
|
|
* @return double|int Range of the passed arguments.
|
|
*/
|
|
public static function range( ...$args ) /* : float|int */ {
|
|
sort( $args );
|
|
return end( $args ) - reset( $args );
|
|
}
|
|
|
|
/**
|
|
* Find the maximum value of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the maximum value shall be found.
|
|
* @return double|int Maximum value of the passed arguments.
|
|
*/
|
|
public static function max( ...$args ) /* : float|int */ {
|
|
return max( $args );
|
|
}
|
|
|
|
/**
|
|
* Find the minimum value of the arguments.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int ...$args Values for which the minimum value shall be found.
|
|
* @return double|int Minimum value of the passed arguments.
|
|
*/
|
|
public static function min( ...$args ) /* : float|int */ {
|
|
return min( $args );
|
|
}
|
|
|
|
/**
|
|
* Calculate the remainder of a division of two numbers.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $op1 First number (dividend).
|
|
* @param double|int $op2 Second number (divisor).
|
|
* @return int Remainder of the division (dividend / divisor).
|
|
*/
|
|
public static function mod( $op1, $op2 ): int {
|
|
return $op1 % $op2;
|
|
}
|
|
|
|
/**
|
|
* Calculate the power of a base and an exponent.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $base Base.
|
|
* @param double|int $exponent Exponent.
|
|
* @return double|int Power base^exponent.
|
|
*/
|
|
public static function power( $base, $exponent ) /* : float|int */ {
|
|
return pow( $base, $exponent );
|
|
}
|
|
|
|
/**
|
|
* Calculate the logarithm of a number to a base.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $number Number.
|
|
* @param double|int $base Optional. Base for the logarithm. Default e (for the natural logarithm).
|
|
* @return double Logarithm of the number to the base.
|
|
*/
|
|
public static function log( $number, $base = M_E ): float {
|
|
return log( $number, $base );
|
|
}
|
|
|
|
/**
|
|
* Calculate the arc tangent of two variables.
|
|
*
|
|
* The signs of the numbers determine the quadrant of the result.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $op1 First number.
|
|
* @param double|int $op2 Second number.
|
|
* @return double Arc tangent of two numbers, similar to arc tangent of $op1/op$ except for the sign.
|
|
*/
|
|
public static function atan2( $op1, $op2 ): float {
|
|
return atan2( $op1, $op2 );
|
|
}
|
|
|
|
/**
|
|
* Round a number to a given precision.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $value Number to be rounded.
|
|
* @param int $decimals Optional. Number of decimals after the comma after the rounding.
|
|
* @return double Rounded number.
|
|
*/
|
|
public static function round( $value, $decimals = 0 ): float {
|
|
return round( $value, $decimals );
|
|
}
|
|
|
|
/**
|
|
* Format a number with the . as the decimal separator and the , as the thousand separator, rounded to a precision.
|
|
*
|
|
* The is the common number format in English-language regions.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $value Number to be rounded and formatted.
|
|
* @param int $decimals Optional. Number of decimals after the decimal separator after the rounding.
|
|
* @return string Formatted number.
|
|
*/
|
|
public static function number_format( $value, $decimals = 0 ): string {
|
|
return number_format( $value, $decimals, '.', ',' );
|
|
}
|
|
|
|
/**
|
|
* Format a number with the , as the decimal separator and the space as the thousand separator, rounded to a precision.
|
|
*
|
|
* The is the common number format in non-English-language regions, mainly in Europe.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param double|int $value Number to be rounded and formatted.
|
|
* @param int $decimals Optional. Number of decimals after the decimal separator after the rounding.
|
|
* @return string Formatted number.
|
|
*/
|
|
public static function number_format_eu( $value, $decimals = 0 ): string {
|
|
return number_format( $value, $decimals, ',', ' ' );
|
|
}
|
|
|
|
/**
|
|
* Set the seed for the generation of random numbers.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param string $random_seed The seed.
|
|
*/
|
|
protected static function _set_random_seed( $random_seed ): void {
|
|
self::$random_seed = $random_seed;
|
|
}
|
|
|
|
/**
|
|
* Get the seed for the generation of random numbers.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @return string The seed.
|
|
*/
|
|
protected static function _get_random_seed(): string {
|
|
if ( is_null( self::$random_seed ) ) {
|
|
return microtime();
|
|
}
|
|
return self::$random_seed;
|
|
}
|
|
|
|
/**
|
|
* Get a random integer from a range.
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @param int $min Minimum value for the range.
|
|
* @param int $max Maximum value for the range.
|
|
* @return int Random integer from the range [$min, $max].
|
|
*/
|
|
public static function rand_int( $min, $max ): int {
|
|
// Swap min and max value if min is bigger than max.
|
|
if ( $min > $max ) {
|
|
$tmp = $max;
|
|
$max = $min;
|
|
$min = $tmp;
|
|
unset( $tmp );
|
|
}
|
|
$number_characters = (int) ceil( log( $max + 1 - $min, 16 ) );
|
|
$md5string = md5( self::_get_random_seed() );
|
|
$offset = 0;
|
|
do {
|
|
while ( ( $offset + $number_characters ) > strlen( $md5string ) ) { // phpcs:ignore Squiz.PHP.DisallowSizeFunctionsInLoops.Found
|
|
$md5string .= md5( $md5string );
|
|
}
|
|
$random_number = (int) hexdec( substr( $md5string, $offset, $number_characters ) );
|
|
$offset += $number_characters;
|
|
} while ( ( $min + $random_number ) > $max );
|
|
return $min + $random_number;
|
|
}
|
|
|
|
/**
|
|
* Get a random double value from a range [0, 1].
|
|
*
|
|
* @since 1.0.0
|
|
*
|
|
* @return double Random number from the range [0, 1].
|
|
*/
|
|
public static function rand_float(): float {
|
|
$random_values = unpack( 'v', md5( self::_get_random_seed(), true ) );
|
|
return array_shift( $random_values ) / 65536; // @phpstan-ignore-line
|
|
}
|
|
|
|
} // class EvalMath_Functions
|