Well tested 'is number' checks, that can optionally include number-like strings, and non-finite values.
npm install @toolbuilder/isnumberWell tested 'is number' checks, that can accept number-like strings, and non-finite values as desired.
There are a lot of is number tests out there. Many of them don't work quite right. Others use a different
definition of is number than you might want. So after spending way too much time for such a simple thing,
here are four checks:
|Function |number literals|number-like strings|Infinity and NaN|Infinity and NaN strings|other strings|
|----------------|---------------|-------------------|----------------|------------------------|-------------|
|isNumeric |true |true |true |true |false |
|isNumber |true |false |true |false |false |
|isFiniteNumeric |true |true |false |false |false |
|isFiniteNumber |true |false |false |false |false |
* Installation
* Getting Started
* API
* isNumber
* isNumeric
* isFiniteNumber
* isFiniteNumeric
* Credits
* Contributing
* Issues
* License
``bash`
npm install --save @toolbuilder/isnumber
This is a dual package,
so named exports are available for both CommonJS and ES modules.
`javascript
import { isNumeric, isFiniteNumeric, isNumber, isFiniteNumber } from '@toolbuilder/isnumber'
console.log(isNumeric('1.234')) // true because it looks like a number
console.log(isFiniteNumeric(42.54)) // true
console.log(isNumber('1.234')) // false because it is a string
console.log(isFiniteNumber(-Infinity)) // false
`
API documentation follows.
Test if n is a number.
Includes Infinities and NaN, does not include strings that look like numbers
Parameters:
* n any value to test
`javascript`
isNumber(1.23) // true
isNumber(Infinity) // true
isNumber(NaN) // true
isNumber('1.23') // false
Returns [boolean][1] true if is number, false otherwise
Test if n is a number, or string that parses to a number. Includes infinities and NaN.
Non-finite strings are: 'Infinity', '-Infinity', and 'NaN'.
Parameters:
* n any value to test
`javascript`
isNumeric(1.23) // true
isNumeric('Infinity') // true
isNumeric(NaN) // true
isNumeric('1.23') // true
isNumeric('hi') // false
Returns [boolean][1] true if is numeric, false otherwise
Test if n is a finite number.
Does not include infinities, NaN, or strings that look like numbers.
Parameters:
* n any value to test
`javascript`
isFiniteNumber(1.23) // true
isFiniteNumber(Infinity) // false
isFiniteNumber(NaN) // false
isFiniteNumber('1.23') // false
Returns [boolean][1] true if is a finite number, false otherwise
Test if n is a finite number, or string that parses to a finite number.
Does not include infinities, NaN
Parameters:
* n any value to test
`javascript`
isFiniteNumeric(1.23) // true
isFiniteNumeric('Infinity') // false
isFiniteNumeric(NaN) // false
isFiniteNumeric('1.23') // true
isFiniteNumeric('hi') // false
Returns [boolean][1] true if is a finite number, false otherwise
[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
The isFiniteNumeric implementation, and the most of the tests were copied from this
site. I found these tests on Stack Overflow
in an answer by 'CMS'. Thanks!
Contributions are welcome. Please create a pull request.
* I use pnpm instead of npm.
* Run the unit tests with pnpm test
* Package verification requires pnpm to be installed globally.
*
*
to build cjs, docs, and .d.tspnpm run check:packfile
* to test against ES and CommonJS projects, as well as Electronpnpm run check` to validate the package is ready for commit
*
This project uses Github issues.
MIT