"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.createSimplifyConstant = void 0; var _is = require("../../utils/is.js"); var _factory = require("../../utils/factory.js"); var _number = require("../../utils/number.js"); var _util = require("./simplify/util.js"); var _noop = require("../../utils/noop.js"); const name = 'simplifyConstant'; const dependencies = ['typed', 'config', 'mathWithTransform', 'matrix', '?fraction', '?bignumber', 'AccessorNode', 'ArrayNode', 'ConstantNode', 'FunctionNode', 'IndexNode', 'ObjectNode', 'OperatorNode', 'SymbolNode']; const createSimplifyConstant = exports.createSimplifyConstant = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => { let { typed, config, mathWithTransform, matrix, fraction, bignumber, AccessorNode, ArrayNode, ConstantNode, FunctionNode, IndexNode, ObjectNode, OperatorNode, SymbolNode } = _ref; const { isCommutative, isAssociative, allChildren, createMakeNodeFunction } = (0, _util.createUtil)({ FunctionNode, OperatorNode, SymbolNode }); /** * simplifyConstant() takes a mathjs expression (either a Node representing * a parse tree or a string which it parses to produce a node), and replaces * any subexpression of it consisting entirely of constants with the computed * value of that subexpression. * * Syntax: * * math.simplifyConstant(expr) * math.simplifyConstant(expr, options) * * Examples: * * math.simplifyConstant('x + 4*3/6') // Node "x + 2" * math.simplifyConstant('z cos(0)') // Node "z 1" * math.simplifyConstant('(5.2 + 1.08)t', {exactFractions: false}) // Node "6.28 t" * * See also: * * simplify, simplifyCore, resolve, derivative * * @param {Node | string} node * The expression to be simplified * @param {Object} options * Simplification options, as per simplify() * @return {Node} Returns expression with constant subexpressions evaluated */ const simplifyConstant = typed('simplifyConstant', { Node: node => _ensureNode(foldFraction(node, {})), 'Node, Object': function (expr, options) { return _ensureNode(foldFraction(expr, options)); } }); function _removeFractions(thing) { if ((0, _is.isFraction)(thing)) { return thing.valueOf(); } if (thing instanceof Array) { return thing.map(_removeFractions); } if ((0, _is.isMatrix)(thing)) { return matrix(_removeFractions(thing.valueOf())); } return thing; } function _eval(fnname, args, options) { try { return mathWithTransform[fnname].apply(null, args); } catch (ignore) { // sometimes the implicit type conversion causes the evaluation to fail, so we'll try again after removing Fractions args = args.map(_removeFractions); return _toNumber(mathWithTransform[fnname].apply(null, args), options); } } const _toNode = typed({ Fraction: _fractionToNode, number: function (n) { if (n < 0) { return unaryMinusNode(new ConstantNode(-n)); } return new ConstantNode(n); }, BigNumber: function (n) { if (n < 0) { return unaryMinusNode(new ConstantNode(-n)); } return new ConstantNode(n); // old parameters: (n.toString(), 'number') }, bigint: function (n) { if (n < 0n) { return unaryMinusNode(new ConstantNode(-n)); } return new ConstantNode(n); }, Complex: function (s) { throw new Error('Cannot convert Complex number to Node'); }, string: function (s) { return new ConstantNode(s); }, Matrix: function (m) { return new ArrayNode(m.valueOf().map(e => _toNode(e))); } }); function _ensureNode(thing) { if ((0, _is.isNode)(thing)) { return thing; } return _toNode(thing); } // convert a number to a fraction only if it can be expressed exactly, // and when both numerator and denominator are small enough function _exactFraction(n, options) { const exactFractions = options && options.exactFractions !== false; if (exactFractions && isFinite(n) && fraction) { const f = fraction(n); const fractionsLimit = options && typeof options.fractionsLimit === 'number' ? options.fractionsLimit : Infinity; // no limit by default if (f.valueOf() === n && f.n < fractionsLimit && f.d < fractionsLimit) { return f; } } return n; } // Convert numbers to a preferred number type in preference order: Fraction, number, Complex // BigNumbers are left alone const _toNumber = typed({ 'string, Object': function (s, options) { const numericType = (0, _number.safeNumberType)(s, config); if (numericType === 'BigNumber') { if (bignumber === undefined) { (0, _noop.noBignumber)(); } return bignumber(s); } else if (numericType === 'bigint') { return BigInt(s); } else if (numericType === 'Fraction') { if (fraction === undefined) { (0, _noop.noFraction)(); } return fraction(s); } else { const n = parseFloat(s); return _exactFraction(n, options); } }, 'Fraction, Object': function (s, options) { return s; }, // we don't need options here 'BigNumber, Object': function (s, options) { return s; }, // we don't need options here 'number, Object': function (s, options) { return _exactFraction(s, options); }, 'bigint, Object': function (s, options) { return s; }, 'Complex, Object': function (s, options) { if (s.im !== 0) { return s; } return _exactFraction(s.re, options); }, 'Matrix, Object': function (s, options) { return matrix(_exactFraction(s.valueOf())); }, 'Array, Object': function (s, options) { return s.map(_exactFraction); } }); function unaryMinusNode(n) { return new OperatorNode('-', 'unaryMinus', [n]); } function _fractionToNode(f) { // note: we convert await from bigint values, because bigint values gives issues with divisions: 1n/2n=0n and not 0.5 const fromBigInt = value => config.number === 'BigNumber' && bignumber ? bignumber(value) : Number(value); const numeratorValue = f.s * f.n; const numeratorNode = numeratorValue < 0n ? new OperatorNode('-', 'unaryMinus', [new ConstantNode(-fromBigInt(numeratorValue))]) : new ConstantNode(fromBigInt(numeratorValue)); return f.d === 1n ? numeratorNode : new OperatorNode('/', 'divide', [numeratorNode, new ConstantNode(fromBigInt(f.d))]); } /* Handles constant indexing of ArrayNodes, matrices, and ObjectNodes */ function _foldAccessor(obj, index, options) { if (!(0, _is.isIndexNode)(index)) { // don't know what to do with that... return new AccessorNode(_ensureNode(obj), _ensureNode(index)); } if ((0, _is.isArrayNode)(obj) || (0, _is.isMatrix)(obj)) { const remainingDims = Array.from(index.dimensions); /* We will resolve constant indices one at a time, looking * just in the first or second dimensions because (a) arrays * of more than two dimensions are likely rare, and (b) pulling * out the third or higher dimension would be pretty intricate. * The price is that we miss simplifying [..3d array][x,y,1] */ while (remainingDims.length > 0) { if ((0, _is.isConstantNode)(remainingDims[0]) && typeof remainingDims[0].value !== 'string') { const first = _toNumber(remainingDims.shift().value, options); if ((0, _is.isArrayNode)(obj)) { obj = obj.items[first - 1]; } else { // matrix obj = obj.valueOf()[first - 1]; if (obj instanceof Array) { obj = matrix(obj); } } } else if (remainingDims.length > 1 && (0, _is.isConstantNode)(remainingDims[1]) && typeof remainingDims[1].value !== 'string') { const second = _toNumber(remainingDims[1].value, options); const tryItems = []; const fromItems = (0, _is.isArrayNode)(obj) ? obj.items : obj.valueOf(); for (const item of fromItems) { if ((0, _is.isArrayNode)(item)) { tryItems.push(item.items[second - 1]); } else if ((0, _is.isMatrix)(obj)) { tryItems.push(item[second - 1]); } else { break; } } if (tryItems.length === fromItems.length) { if ((0, _is.isArrayNode)(obj)) { obj = new ArrayNode(tryItems); } else { // matrix obj = matrix(tryItems); } remainingDims.splice(1, 1); } else { // extracting slice along 2nd dimension failed, give up break; } } else { // neither 1st or 2nd dimension is constant, give up break; } } if (remainingDims.length === index.dimensions.length) { /* No successful constant indexing */ return new AccessorNode(_ensureNode(obj), index); } if (remainingDims.length > 0) { /* Indexed some but not all dimensions */ index = new IndexNode(remainingDims); return new AccessorNode(_ensureNode(obj), index); } /* All dimensions were constant, access completely resolved */ return obj; } if ((0, _is.isObjectNode)(obj) && index.dimensions.length === 1 && (0, _is.isConstantNode)(index.dimensions[0])) { const key = index.dimensions[0].value; if (key in obj.properties) { return obj.properties[key]; } return new ConstantNode(); // undefined } /* Don't know how to index this sort of obj, at least not with this index */ return new AccessorNode(_ensureNode(obj), index); } /* * Create a binary tree from a list of Fractions and Nodes. * Tries to fold Fractions by evaluating them until the first Node in the list is hit, so * `args` should be sorted to have the Fractions at the start (if the operator is commutative). * @param args - list of Fractions and Nodes * @param fn - evaluator for the binary operation evaluator that accepts two Fractions * @param makeNode - creates a binary OperatorNode/FunctionNode from a list of child Nodes * if args.length is 1, returns args[0] * @return - Either a Node representing a binary expression or Fraction */ function foldOp(fn, args, makeNode, options) { const first = args.shift(); // In the following reduction, sofar always has one of the three following // forms: [NODE], [CONSTANT], or [NODE, CONSTANT] const reduction = args.reduce((sofar, next) => { if (!(0, _is.isNode)(next)) { const last = sofar.pop(); if ((0, _is.isNode)(last)) { return [last, next]; } // Two constants in a row, try to fold them into one try { sofar.push(_eval(fn, [last, next], options)); return sofar; } catch (ignoreandcontinue) { sofar.push(last); // fall through to Node case } } // Encountered a Node, or failed folding -- // collapse everything so far into a single tree: sofar.push(_ensureNode(sofar.pop())); const newtree = sofar.length === 1 ? sofar[0] : makeNode(sofar); return [makeNode([newtree, _ensureNode(next)])]; }, [first]); if (reduction.length === 1) { return reduction[0]; } // Might end up with a tree and a constant at the end: return makeNode([reduction[0], _toNode(reduction[1])]); } // destroys the original node and returns a folded one function foldFraction(node, options) { switch (node.type) { case 'SymbolNode': return node; case 'ConstantNode': switch (typeof node.value) { case 'number': return _toNumber(node.value, options); case 'bigint': return _toNumber(node.value, options); case 'string': return node.value; default: if (!isNaN(node.value)) return _toNumber(node.value, options); } return node; case 'FunctionNode': if (mathWithTransform[node.name] && mathWithTransform[node.name].rawArgs) { return node; } { // Process operators as OperatorNode const operatorFunctions = ['add', 'multiply']; if (!operatorFunctions.includes(node.name)) { const args = node.args.map(arg => foldFraction(arg, options)); // If all args are numbers if (!args.some(_is.isNode)) { try { return _eval(node.name, args, options); } catch (ignoreandcontinue) {} } // Size of a matrix does not depend on entries if (node.name === 'size' && args.length === 1 && (0, _is.isArrayNode)(args[0])) { const sz = []; let section = args[0]; while ((0, _is.isArrayNode)(section)) { sz.push(section.items.length); section = section.items[0]; } return matrix(sz); } // Convert all args to nodes and construct a symbolic function call return new FunctionNode(node.name, args.map(_ensureNode)); } else { // treat as operator } } /* falls through */ case 'OperatorNode': { const fn = node.fn.toString(); let args; let res; const makeNode = createMakeNodeFunction(node); if ((0, _is.isOperatorNode)(node) && node.isUnary()) { args = [foldFraction(node.args[0], options)]; if (!(0, _is.isNode)(args[0])) { res = _eval(fn, args, options); } else { res = makeNode(args); } } else if (isAssociative(node, options.context)) { args = allChildren(node, options.context); args = args.map(arg => foldFraction(arg, options)); if (isCommutative(fn, options.context)) { // commutative binary operator const consts = []; const vars = []; for (let i = 0; i < args.length; i++) { if (!(0, _is.isNode)(args[i])) { consts.push(args[i]); } else { vars.push(args[i]); } } if (consts.length > 1) { res = foldOp(fn, consts, makeNode, options); vars.unshift(res); res = foldOp(fn, vars, makeNode, options); } else { // we won't change the children order since it's not neccessary res = foldOp(fn, args, makeNode, options); } } else { // non-commutative binary operator res = foldOp(fn, args, makeNode, options); } } else { // non-associative binary operator args = node.args.map(arg => foldFraction(arg, options)); res = foldOp(fn, args, makeNode, options); } return res; } case 'ParenthesisNode': // remove the uneccessary parenthesis return foldFraction(node.content, options); case 'AccessorNode': return _foldAccessor(foldFraction(node.object, options), foldFraction(node.index, options), options); case 'ArrayNode': { const foldItems = node.items.map(item => foldFraction(item, options)); if (foldItems.some(_is.isNode)) { return new ArrayNode(foldItems.map(_ensureNode)); } /* All literals -- return a Matrix so we can operate on it */ return matrix(foldItems); } case 'IndexNode': { return new IndexNode(node.dimensions.map(n => simplifyConstant(n, options))); } case 'ObjectNode': { const foldProps = {}; for (const prop in node.properties) { foldProps[prop] = simplifyConstant(node.properties[prop], options); } return new ObjectNode(foldProps); } case 'AssignmentNode': /* falls through */ case 'BlockNode': /* falls through */ case 'FunctionAssignmentNode': /* falls through */ case 'RangeNode': /* falls through */ case 'ConditionalNode': /* falls through */ default: throw new Error(`Unimplemented node type in simplifyConstant: ${node.type}`); } } return simplifyConstant; });