1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465 |
- "use strict";
- Object.defineProperty(exports, "__esModule", {
- value: true
- });
- exports.createSymbolicEqual = void 0;
- var _is = require("../../utils/is.js");
- var _factory = require("../../utils/factory.js");
- var name = 'symbolicEqual';
- var dependencies = ['parse', 'simplify', 'typed', 'OperatorNode'];
- var createSymbolicEqual = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
- var parse = _ref.parse,
- simplify = _ref.simplify,
- typed = _ref.typed,
- OperatorNode = _ref.OperatorNode;
- /**
- * Attempts to determine if two expressions are symbolically equal, i.e.
- * one is the result of valid algebraic manipulations on the other.
- * Currently, this simply checks if the difference of the two expressions
- * simplifies down to 0. So there are two important caveats:
- * 1. whether two expressions are symbolically equal depends on the
- * manipulations allowed. Therefore, this function takes an optional
- * third argument, which are the options that control the behavior
- * as documented for the `simplify()` function.
- * 2. it is in general intractable to find the minimal simplification of
- * an arbitrarily complicated expression. So while a `true` value
- * of `symbolicEqual` ensures that the two expressions can be manipulated
- * to match each other, a `false` value does not absolutely rule this out.
- *
- * Syntax:
- *
- * symbolicEqual(expr1, expr2)
- * symbolicEqual(expr1, expr2, options)
- *
- * Examples:
- *
- * symbolicEqual('x*y', 'y*x') // Returns true
- * symbolicEqual('x*y', 'y*x', {context: {multiply: {commutative: false}}}) // Returns false
- * symbolicEqual('x/y', '(y*x^(-1))^(-1)') // Returns true
- * symbolicEqual('abs(x)','x') // Returns false
- * symbolicEqual('abs(x)','x', simplify.positiveContext) // Returns true
- *
- * See also:
- *
- * simplify, evaluate
- *
- * @param {Node|string} expr1 The first expression to compare
- * @param {Node|string} expr2 The second expression to compare
- * @param {Object} [options] Optional option object, passed to simplify
- * @returns {boolean}
- * Returns true if a valid manipulation making the expressions equal
- * is found.
- */
- function _symbolicEqual(e1, e2) {
- var options = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {};
- var diff = new OperatorNode('-', 'subtract', [e1, e2]);
- var simplified = simplify(diff, {}, options);
- return (0, _is.isConstantNode)(simplified) && !simplified.value;
- }
- return typed(name, {
- 'Node, Node': _symbolicEqual,
- 'Node, Node, Object': _symbolicEqual
- });
- });
- exports.createSymbolicEqual = createSymbolicEqual;
|