/** * LogarithmPlotter - 2D plotter software to make BODE plots, sequences and distribution functions. * Copyright (C) 2021-2024 Ad5001 * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ // Load prior tests import "./base.mjs" import { describe, it } from "mocha" import { expect } from "chai" import ExprEval from "../../src/module/expreval.mjs" describe("Module/ExprEval", function() { describe("#parse", function() { const evaluate = (expr, vals) => ExprEval.parse(expr).evaluate(vals) it("parses simple mathematical expressions", function() { expect(evaluate("1", {})).to.equal(1) expect(evaluate("-1", {})).to.equal(-1) expect(evaluate("-(-1)", {})).to.equal(1) expect(evaluate("+(-1)", {})).to.equal(-1) expect(evaluate("3!", {})).to.equal(6) expect(evaluate("1+1", {})).to.equal(2) expect(evaluate("4*3", {})).to.equal(12) expect(evaluate("64/4", {})).to.equal(16) expect(evaluate("2^10", {})).to.equal(1024) expect(evaluate("10%3", {})).to.equal(1) expect(evaluate("10%3", {})).to.equal(1) // Test priorities expect(evaluate("10*10+10*10", {})).to.equal(200) expect(evaluate("10/10+10/10", {})).to.equal(2) expect(evaluate("10/10+10/10", {})).to.equal(2) expect(evaluate("2^2-2^2", {})).to.equal(0) expect(evaluate("(2^2-2)^2", {})).to.equal(4) }) it("parses equality and test statements", function() { expect(evaluate("10%3 == 1 ? 2 : 1", {})).to.equal(2) expect(evaluate("10%3 != 1 ? 2 : 1", {})).to.equal(1) expect(evaluate("10 < 3 ? 2 : 1", {})).to.equal(1) expect(evaluate("10 > 3 ? (2+1) : 1", {})).to.equal(3) expect(evaluate("10 <= 3 ? 4 : 1", {})).to.equal(1) expect(evaluate("10 >= 3 ? 4 : 1", {})).to.equal(4) // Check equality expect(evaluate("10 < 10 ? 2 : 1", {})).to.equal(1) expect(evaluate("10 > 10 ? 2 : 1", {})).to.equal(1) expect(evaluate("10 <= 10 ? 4 : 1", {})).to.equal(4) expect(evaluate("10 >= 10 ? 4 : 1", {})).to.equal(4) // Check 'and' and 'or' expect(evaluate("10 <= 3 and 10 < 10 ? 4 : 1", {})).to.equal(1) expect(evaluate("10 <= 10 and 10 < 10 ? 4 : 1", {})).to.equal(1) expect(evaluate("10 <= 10 and 10 < 20 ? 4 : 1", {})).to.equal(4) expect(evaluate("10 <= 3 or 10 < 10 ? 4 : 1", {})).to.equal(1) expect(evaluate("10 <= 10 or 10 < 10 ? 4 : 1", {})).to.equal(4) expect(evaluate("10 <= 10 or 10 < 20 ? 4 : 1", {})).to.equal(4) }) it("parses singular function operators (functions with one arguments and no parenthesis)", function() { // Trigonometric functions expect(evaluate("sin π", { })).to.be.approximately(0, Number.EPSILON) expect(evaluate("cos π", { })).to.be.approximately(-1, Number.EPSILON) expect(evaluate("tan π", { })).to.be.approximately(0, Number.EPSILON) expect(evaluate("asin 1", { })).to.be.approximately(Math.PI/2, Number.EPSILON) expect(evaluate("acos 1", { })).to.be.approximately(0, Number.EPSILON) expect(evaluate("atan 1", { })).to.be.approximately(Math.PI/4, Number.EPSILON) expect(evaluate("sinh 1", { })).to.be.approximately(Math.sinh(1), Number.EPSILON) expect(evaluate("cosh 1", { })).to.be.approximately(Math.cosh(1), Number.EPSILON) expect(evaluate("tanh 1", { })).to.be.approximately(Math.tanh(1), Number.EPSILON) expect(evaluate("asinh 1", { })).to.be.approximately(Math.asinh(1), Number.EPSILON) expect(evaluate("acosh 1", { })).to.be.approximately(Math.acosh(1), Number.EPSILON) expect(evaluate("atanh 0.5", { })).to.be.approximately(Math.atanh(0.5), Number.EPSILON) // Reverse trigonometric expect(evaluate("asin sin 1", { })).to.be.approximately(1, Number.EPSILON) expect(evaluate("acos cos 1", { })).to.be.approximately(1, Number.EPSILON) expect(evaluate("atan tan 1", { })).to.be.approximately(1, Number.EPSILON) expect(evaluate("asinh sinh 1", { })).to.be.approximately(1, Number.EPSILON) expect(evaluate("acosh cosh 1", { })).to.be.approximately(1, Number.EPSILON) expect(evaluate("atanh tanh 1", { })).to.be.approximately(1, Number.EPSILON) // Other functions }) }) describe("#integral", function() { it("returns the integral value between two integers", function() { expect(ExprEval.integral(0, 1, "1", "t")).to.be.approximately(1, Number.EPSILON) expect(ExprEval.integral(0, 1, "t", "t")).to.be.approximately(1 / 2, Number.EPSILON) expect(ExprEval.integral(0, 1, "t^2", "t")).to.be.approximately(1 / 3, Number.EPSILON) expect(ExprEval.integral(0, 1, "t^3", "t")).to.be.approximately(1 / 4, 0.01) expect(ExprEval.integral(0, 1, "t^4", "t")).to.be.approximately(1 / 5, 0.01) expect(ExprEval.integral(10, 40, "1", "t")).to.equal(30) expect(ExprEval.integral(20, 40, "1", "t")).to.equal(20) expect(ExprEval.integral(0, 10, { execute: (x) => 1 })).to.equal(10) expect(ExprEval.integral(0, 10, { execute: (x) => x })).to.equal(50) expect(ExprEval.integral(0, 1, { execute: (x) => Math.pow(x, 2) })).to.equal(1 / 3) }) it("throws error when provided with invalid arguments", function() { const noArg1 = () => ExprEval.integral() const noArg2 = () => ExprEval.integral(0) const noFunction = () => ExprEval.integral(0, 1) const invalidObjectProvided = () => ExprEval.integral(0, 1, { a: 2 }) const notAnObjectProvided = () => ExprEval.integral(0, 1, "string") const invalidFromProvided = () => ExprEval.integral("ze", 1, "t^2", "t") const invalidToProvided = () => ExprEval.integral(0, "ze", "t^2", "t") const notStringProvided1 = () => ExprEval.integral(0, 1, { a: 2 }, { b: 1 }) const notStringProvided2 = () => ExprEval.integral(0, 1, { a: 2 }, "t") const notStringProvided3 = () => ExprEval.integral(0, 1, "t^2", { b: 1 }) const invalidVariableProvided = () => ExprEval.integral(0, 1, "t^2", "93IO74") const invalidExpressionProvided = () => ExprEval.integral(0, 1, "t^2t", "t") const invalidVariableInExpression = () => ExprEval.integral(0, 1, "t^2+x", "t") expect(noArg1).to.throw() expect(noArg2).to.throw() expect(noFunction).to.throw() expect(invalidObjectProvided).to.throw() expect(invalidFromProvided).to.throw() expect(invalidToProvided).to.throw() expect(notAnObjectProvided).to.throw() expect(notStringProvided1).to.throw() expect(notStringProvided2).to.throw() expect(notStringProvided3).to.throw() expect(invalidVariableProvided).to.throw() expect(invalidExpressionProvided).to.throw() expect(invalidVariableInExpression).to.throw() }) }) describe("#derivative", function() { const DELTA = 1e-5 it("returns the derivative value between two integers", function() { expect(ExprEval.derivative("1", "t", 2)).to.be.approximately(0, DELTA) expect(ExprEval.derivative("t", "t", 2)).to.be.approximately(1, DELTA) expect(ExprEval.derivative("t^2", "t", 2)).to.be.approximately(4, DELTA) expect(ExprEval.derivative("t^3", "t", 2)).to.be.approximately(12, DELTA) expect(ExprEval.derivative("t^4", "t", 2)).to.be.approximately(32, DELTA) expect(ExprEval.derivative({ execute: (x) => 1 }, 10)).to.equal(0) expect(ExprEval.derivative({ execute: (x) => x }, 10)).to.be.approximately(1, DELTA) expect(ExprEval.derivative({ execute: (x) => Math.pow(x, 2) }, 10)).to.be.approximately(20, DELTA) }) it("throws error when provided with invalid arguments", function() { const noArg1 = () => ExprEval.derivative() const noArg2 = () => ExprEval.derivative("1") const noValue1 = () => ExprEval.derivative("0", "1") const noValue2 = () => ExprEval.derivative({ execute: (x) => 1 }) const invalidObjectProvided = () => ExprEval.derivative({ a: 2 }, 1) const notAnObjectProvided = () => ExprEval.derivative("string", 1) const invalidXProvided = () => ExprEval.derivative("t^2+x", "t", "ze") const notStringProvided1 = () => ExprEval.derivative({ a: 2 }, { b: 1 }, 1) const notStringProvided2 = () => ExprEval.derivative({ a: 2 }, "t", 1) const notStringProvided3 = () => ExprEval.derivative("t^2", { b: 1 }, 1) const invalidVariableProvided = () => ExprEval.derivative("t^2", "93IO74", 1) const invalidExpressionProvided = () => ExprEval.derivative("t^2t", "t", 1) const invalidVariableInExpression = () => ExprEval.derivative("t^2+x", "t", 1) expect(noArg1).to.throw() expect(noArg2).to.throw() expect(noValue1).to.throw() expect(noValue2).to.throw() expect(invalidObjectProvided).to.throw() expect(invalidXProvided).to.throw() expect(notAnObjectProvided).to.throw() expect(notStringProvided1).to.throw() expect(notStringProvided2).to.throw() expect(notStringProvided3).to.throw() expect(invalidVariableProvided).to.throw() expect(invalidExpressionProvided).to.throw() expect(invalidVariableInExpression).to.throw() }) }) })