isxxxx


Lightweight library for checking number properties and mathematical classifications.

Installation

``bash
npm install isxxxx


or

yarn add isxxxx

or

pnpm add isxxxx
`

Usage

`javascript
// Import specific functions
const { isEven, isPrime, isHappy } = require('isxxxx');

// Or import everything
const isxxxx = require('isxxxx');

// Examples
isEven(4); // true
isPrime(17); // true
isFibonacci(8); // true
isHappy(19); // true
`

Available Functions

$3


- isEven(num) - Checks if number is even
- isOdd(num) - Checks if number is odd
- isPositive(num) - Checks if number is positive
- isNegative(num) - Checks if number is negative
- isZero(num) - Checks if number is zero
- isInteger(num) - Checks if number is an integer
- isSafeInteger(num) - Checks if number is a safe integer in JavaScript
- isInRange(num, min, max) - Checks if number is within range (inclusive)

$3

- isPrime(num) - Checks if number is prime
- isPerfectSquare(num) - Checks if number is a perfect square
- isMultipleOf(num, multiple) - Checks if number is a multiple of another
- isPowerOfTwo(num) - Checks if number is a power of two
- isPowerOf(num, base) - Checks if number is a power of a given base
- isSquareFree(num) - Checks if number has no squared prime factors

$3

- isFibonacci(num) - Checks if number is in the Fibonacci sequence
- isLucas(num) - Checks if number is in the Lucas sequence
- isCatalan(num) - Checks if number is a Catalan number
- isBell(num) - Checks if number is a Bell number
- isTriangular(num) - Checks if number is triangular (1+2+3+...)
- isPentagonal(num) - Checks if number is pentagonal
- isHexagonal(num) - Checks if number is hexagonal
- isFactorial(num) - Checks if number is a factorial (n!)
- isRepunit(num) - Checks if number consists only of 1s
- isPronic(num) - Checks if number is pronic (n*(n+1))

$3

- isMersennePrime(num) - Checks if number is a Mersenne prime (2^n-1)
- isFermat(num) - Checks if number is a Fermat number (2^(2^n)+1)
- isCullen(num) - Checks if number is a Cullen number (n*2^n+1)
- isWoodall(num) - Checks if number is a Woodall number (n*2^n-1)
- isKaprekar(num) - Checks if number is a Kaprekar number
- isArmstrong(num) - Checks if number equals sum of its digits each raised to power of number of digits
- isNarcissistic(num) - Alias for isArmstrong
- isHappy(num) - Checks if a number is "happy" (process leads to 1)
- isHarshad(num) - Checks if number is divisible by sum of its digits
- isSmith(num) - Checks if digit sum equals digit sum of prime factors
- isApocalyptic(num) - Checks if 2^n contains "666"

$3

- isPerfect(num) - Checks if number equals sum of its proper divisors
- isAbundant(num) - Checks if number is less than sum of proper divisors
- isDeficient(num) - Checks if number is greater than sum of proper divisors
- isPowerful(num) - Checks if all prime factors also divide as squares
- isPractical(num) - Checks if every smaller number is sum of distinct divisors
- isSelfNumber(num) - Checks if number cannot be generated as n+sum(digits(n))
- isAutomorphic(num) - Checks if square ends with the number itself
- isPalindrome(num) - Checks if number reads the same forward and backward
- isAlternating(num) - Checks if digits alternate between odd and even
- isUndulant(num) - Checks if digits rise and fall alternately
- isCarmichael(num) - Checks if number satisfies Fermat's little theorem

Error Handling

All functions validate inputs and throw appropriate errors:

`javascript
// Throws TypeError: Expected a number
isEven('not a number');

// Throws TypeError: Expected numbers
isMultipleOf('ten', 5);

// Throws Error: Cannot check for multiples of zero
isMultipleOf(10, 0);
``

License

MIT © Alexander KOP