cmath-js

Implementation of parts of C's & C++'s numerics libraries in TypeScript/JavaScript.

Floating-point functions

• copysign
• fabs
• frexp
• hypot
• ldexp
• nan
• nextafter
• pow

Integer functions

These functions accept either a bigint or an integer number:

• abs
• countl_one as create_countl_one, which is used this way:

  import { create_countl_one } from "cmath-js";
  const countl_one_u16 = create_countl_one({ bits: 16 });
  const integer = 0xF0_00;
  // Prints "1111000000000000 has 4 leading zero bits."
  console.log(`${integer.toString(2).padStart(16, "0")} has ${countl_one_u16(integer)} leading one bits.`);

• countl_zero as create_countl_zero
• countr_one as create_countr_one
• countr_zero as create_countr_zero
• div
• gcd. Example:

  import { gcd } from "cmath-js";
  // Prints "The greatest common divisor of 24 and 32 is 8."
  console.log(`The greatest common divisor of 24 and 32 is ${gcd(24, 32)}.`);

• lcm
• popcount

Functions for both floats and ints

• iota
• signbit

Mathematical constants

• Constants in the std::numbers namespace are available from the numbers.js subpath export. Example:

  import { sqrt3 } from "cmath-js/numbers.js";
  console.log(`The square root of 3 is ${sqrt3}.`);

Test coverage

The test coverage is a perfect 100% and enforced by the publishing and pull request verification workflows.

Contributing

Contributions are welcomed! Feel free to make a pull request. Please add your name to contributors in package.json and run npm run build-and-verify before submitting your PR. By making a pull request you agree to license your contribution under the CC0 license unless otherwise specified.

ESLint is used to enforce code quality and consistent formatting (with the help of Prettier). If ESLint complains when you run npm run build-and-verify, you can run npm run lint-fix to apply automatic fixes and then fix the rest of the errors manually. I recommend configuring your IDE for ESLint and Prettier. If you are using Visual Studio Code, simply installing Microsoft's ESLint extension and the official Prettier extension takes care of that.