What is mathjs?
mathjs is an extensive math library for JavaScript and Node.js. It features a flexible expression parser, a large set of built-in functions, and supports different data types such as numbers, big numbers, complex numbers, fractions, units, and matrices.
What are mathjs's main functionalities?
Basic Arithmetic
Perform basic arithmetic operations like addition, subtraction, multiplication, and division.
const math = require('mathjs');
const sum = math.add(2, 3); // 5
const product = math.multiply(4, 5); // 20
Matrix Operations
Perform operations on matrices such as addition, multiplication, and inversion.
const math = require('mathjs');
const matrix1 = math.matrix([[1, 2], [3, 4]]);
const matrix2 = math.matrix([[5, 6], [7, 8]]);
const result = math.add(matrix1, matrix2); // [[6, 8], [10, 12]]
Complex Numbers
Handle complex numbers and perform arithmetic operations on them.
const math = require('mathjs');
const complex1 = math.complex(2, 3);
const complex2 = math.complex(1, 4);
const sum = math.add(complex1, complex2); // 3 + 7i
Unit Conversions
Convert between different units of measurement.
const math = require('mathjs');
const distance = math.unit(5, 'km');
const convertedDistance = distance.to('mile'); // 3.10685596 mile
Expression Parsing
Parse and evaluate mathematical expressions from strings.
const math = require('mathjs');
const expr = '2 * (3 + 4)';
const result = math.evaluate(expr); // 14
Other packages similar to mathjs
numeric
numeric is a library for numerical computations in JavaScript. It provides functions for matrix operations, solving linear systems, and performing numerical integration. Compared to mathjs, numeric is more focused on numerical methods and less on symbolic computation and unit conversions.
algebrite
algebrite is a JavaScript library for symbolic mathematics. It can perform algebraic operations, calculus, and other symbolic computations. While mathjs also supports some symbolic computation, algebrite is more specialized in this area.
simple-statistics
simple-statistics is a JavaScript library for statistical calculations. It provides functions for descriptive statistics, probability distributions, and regression analysis. Unlike mathjs, which covers a broad range of mathematical functions, simple-statistics is specialized in statistical methods.
https://mathjs.org
Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with different data types like numbers, big numbers, complex numbers, fractions, units, and matrices. Powerful and easy to use.
Features
- Supports numbers, big numbers, complex numbers, fractions, units, strings, arrays, and matrices.
- Is compatible with JavaScript's built-in Math library.
- Contains a flexible expression parser.
- Does symbolic computation.
- Comes with a large set of built-in functions and constants.
- Can be used as a command line application as well.
- Runs on any JavaScript engine.
- Is easily extensible.
- Open source.
Usage
Math.js can be used in both node.js and in the browser.
Install math.js using npm:
npm install mathjs
Or download mathjs via one of the CDN's listed on the downloads page:
https://mathjs.org/download.html
Math.js can be used similar to JavaScript's built-in Math library. Besides that,
math.js can evaluate
expressions
and supports
chained operations.
import {
atan2, chain, derivative, e, evaluate, log, pi, pow, round, sqrt
} from 'mathjs'
round(e, 3)
atan2(3, -3) / pi
log(10000, 10)
sqrt(-4)
pow([[-1, 2], [3, 1]], 2)
derivative('x^2 + x', 'x')
evaluate('12 / (2.3 + 0.7)')
evaluate('12.7 cm to inch')
evaluate('sin(45 deg) ^ 2')
evaluate('9 / 3 + 2i')
evaluate('det([-1, 2; 3, 1])')
chain(3)
.add(4)
.multiply(2)
.done()
See the Getting Started for a more detailed tutorial.
Browser support
Math.js works on any ES6 compatible JavaScript engine, including node.js, Chrome, Firefox, Safari, and Edge.
Documentation
Build
First clone the project from github:
git clone git@github.com:josdejong/mathjs.git
cd mathjs
Install the project dependencies:
npm install
Then, the project can be build by executing the build script via npm:
npm run build
This will build ESM output, CommonJS output, and the bundle math.js
from the source files and put them in the folder lib.
Develop
When developing new features for mathjs, it is good to be aware of the following background information.
Code
The code of mathjs
is written in ES modules, and requires all files to have a real, relative path, meaning the files must have a *.js
extension. Please configure adding file extensions on auto import in your IDE.
Architecture
What mathjs tries to achieve is to offer an environment where you can do calculations with mixed data types,
like multiplying a regular number
with a Complex
number or a BigNumber
, and work with all of those in matrices.
Mathjs also allows to add a new data type, like say BigInt
, with little effort.
The solution that mathjs uses has two main ingredients:
-
Typed functions. All functions are created using typed-function
. This makes it easier to (dynamically) create and extend a single function with new data types, automatically do type conversions on function inputs, etc. So, if you create function multiply for two number
s, you can extend it with support for multiplying two BigInts
. If you define a conversion from BigInt
to number
, the typed-function will automatically allow you to multiply a BigInt
with a number
.
-
Dependency injection. When we have a function multiply
with support for BigInt
, thanks to the dependency injection, other functions using multiply
under the hood, like prod
, will automatically support BigInt
too. This also works the other way around: if you don't need the heavyweight multiply
(which supports BigNumbers, matrices, etc), and you just need a plain and simple number support, you can use a lightweight implementation of multiply
just for numbers, and inject that in prod
and other functions.
At the lowest level, mathjs has immutable factory functions which create immutable functions. The core function math.create(...)
creates a new instance having functions created from all passed factory functions. A mathjs instance is a collection of created functions. It contains a function like math.import
to allow extending the instance with new functions, which can then be used in the expression parser.
Implementing a new function
A common case is to implement a new function. This involves the following steps:
- Implement the function in the right category, for example
./src/function/arithmetic/myNewFunction.js
, where you can replace arithmetic
with the proper category, and myNewFunction
with the name of the new function. Add the new function to the index files ./src/factoriesAny.js
and possibly ./src/factoriesNumber.js
. - Write documentation on the function in the source code comment of
myNewFunction.js
. This documentation is used to auto generate documentation on the website. - Write embedded documentation for the new function in
./src/expression/embeddedDocs/function/arithmetic/myNewFunction.js
. Add the new documentation to the index file ./src/expression/embeddedDocs/embeddedDocs.js
. - Write unit tests for the function in
./test/unit-tests/function/arithmetic/myNewFunction.test.js
. - Write the necessary TypeScript definitions for the new function in
./types/index.d.ts
, and write tests for it in ./test/typescript-tests/testTypes.ts
. This is described in ./types/EXPLANATION.md. - Ensure the code style is ok by running
npm run lint
(run npm run format
to fix the code style automatically).
Build scripts
The build script currently generates two types of output:
- any, generate entry points to create full versions of all functions
- number: generating and entry points to create lightweight functions just supporting
number
For each function, an object is generated containing the factory functions of all dependencies of the function. This allows to just load a specific set of functions, and not load or bundle any other functionality. So for example, to just create function add
you can do math.create(addDependencies)
.
Test
To execute tests for the library, install the project dependencies once:
npm install
Then, the tests can be executed:
npm test
Additionally, the tests can be run on FireFox using headless mode:
npm run test:browser
To run the tests remotely on BrowserStack, first set the environment variables BROWSER_STACK_USERNAME
and BROWSER_STACK_ACCESS_KEY
with your username and access key and then execute:
npm run test:browserstack
You can separately run the code linter, though it is also executed with npm test
:
npm run lint
To automatically fix linting issue, run:
npm run format
To test code coverage of the tests:
npm run coverage
To see the coverage results, open the generated report in your browser:
./coverage/lcov-report/index.html
Continuous integration testing
Continuous integration tests are run on Github Actions and BrowserStack every time a commit is pushed to github. Github Actions runs the tests for different versions of node.js, and BrowserStack runs the tests on all major browsers.
Thanks Github Actions and BrowserStack for the generous free hosting of this open source project!
License
Copyright (C) 2013-2023 Jos de Jong wjosdejong@gmail.com
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
https://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.