extra-bit

The bit is a basic unit of information in information theory, computing.
📦 Node.js, 🌐 Web, 📜 Files, 📰 Docs, 📘 Wiki.

The concept of a bit, which stands for binary digit, has been a fundamental unit of information in the fields of information theory and computing. Bitwise operations are used to manipulate and process data at the bit level, and these operations are crucial for efficient programming in a variety of domains, such as computer graphics and cryptography. JavaScript converts a Number (a 64-bit floating point number) to a 32-bit integer when bitwise operators (such as |) are applied. All bitwise operations are performed on 32-bit integers. This package includes bit twiddling hacks by Sean Eron Anderson and many others.

This package is available in Node.js and Web formats. To use it on the web, simply use the extra_bit global variable after loading with a <script> tag from the jsDelivr CDN.

Stability: Experimental.

const xbit = require('extra-bit');
// import * as xbit from "extra-bit";
// import * as xbit from "https://unpkg.com/extra-bit/index.mjs"; (deno)

xbit.count(7);
// → 3 (111 ⇒ 3)

xbit.parity(8, 2);
// → 2 (10,00 ⇒ 10)

xbit.swap(6, 1, 0);
// → 5 (110 ⇒ 101)

xbit.reverse(0xFFFF0000);
// → 65535 (0x0000FFFF)

xbit.signExtend(15, 4);
// → -1

Index

Property	Description
get	Get bits at specified index.
getAs	Get bits as per mask.
set	Set bits at specified index.
setAs	Set bits as per mask.
toggle	Toggle bits at specified index.
toggleAs	Toggle bits as per mask.
swap	Swap bit sequences at specified indices.
scan	Find index of first set bit from LSB.
scanReverse	Find index of first set bit from MSB.
count	Count bits set.
parity	Calculate n-bit parity.
rotate	Rotate bits by a certain amount.
reverse	Reverse all bits.
merge	Merge bits as per mask.
interleave	Interleave bits of two int16s.
signExtend	Sign extend variable bit-width integer.

References

• Bit Twiddling Hacks by Sean Eron Anderson
• bit-twiddle package by @mikolalysenko