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reDecimalNumber

Regular expression to match a decimal number.

Installation

npm install @stdlib/regexp-decimal-number

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

var reDecimalNumber = require( '@stdlib/regexp-decimal-number' );

reDecimalNumber( [options] )

Returns a regular expression to match a decimal number.

var RE_DECIMAL_NUMBER = reDecimalNumber();

var out = RE_DECIMAL_NUMBER.test( 'foo 1.234.' );
// returns true

out = RE_DECIMAL_NUMBER.test( '2:3' );
// returns false

The function accepts an options object with optional properties:

• flags: string specifying regular expression flags. Default: ''.
• capture: boolean indicating whether to create a capture group for the match. Default: false.

By default, the function returns a regular expression which does not have any flags specified. To specify flags, set the flags option with a list of flags (which may be in any order).

var replace = require( '@stdlib/string-replace' );

var RE_DECIMAL_NUMBER = reDecimalNumber({
    'flags': 'g'
});

var str = 'beep 1.234 boop 1.234';
var out = replace( str, RE_DECIMAL_NUMBER, '' );
// returns 'beep  boop '

By default, the function returns a regular expression which does not capture the part of a string matching the regular expression. To capture matches, set the capture option.

var RE_DECIMAL_NUMBER = reDecimalNumber({
    'capture': true
});

var out = RE_DECIMAL_NUMBER.exec( 'beep 1.234 boop' ).slice();
// returns [ '1.234', '1.234' ]

out = RE_DECIMAL_NUMBER.exec( '' );
// returns null

reDecimalNumber.REGEXP

Regular expression to match a decimal number.

var bool = reDecimalNumber.REGEXP.test( '2:3' );
// returns false

reDecimalNumber.REGEXP_CAPTURE

Regular expression to capture characters matching a decimal number.

var parts = reDecimalNumber.REGEXP_CAPTURE.exec( '1.234' );
// returns [ '1.234', '1.234' ]

Notes

• A leading digit is not required.

  var bool = reDecimalNumber.REGEXP.test( '.5' );
  // returns true

• A decimal point and at least one trailing digit is required.

  var bool = reDecimalNumber.REGEXP.test( '5.' );
  // returns false

• The REGEXP regular expression is defined as

  /[-+]{0,1}[0-9]*\.[0-9]+/
  

• The REGEXP_CAPTURE regular expression is defined as

  /([-+]{0,1}[0-9]*\.[0-9]+)/
  

Examples

var reDecimalNumber = require( '@stdlib/regexp-decimal-number' );

var RE_DECIMAL_NUMBER = reDecimalNumber();

var bool = RE_DECIMAL_NUMBER.test( '1.234' );
// returns true

bool = RE_DECIMAL_NUMBER.test( 'beep 1.234' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '1.234 boop' );
// returns true

bool = RE_DECIMAL_NUMBER.test( 'foo 1.234.' );
// returns true

bool = RE_DECIMAL_NUMBER.test( 'foo 1.234.567.890' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '1.234!' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '0.234' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '.234' );
// returns true

bool = RE_DECIMAL_NUMBER.test( 'beep .234' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '.234 boop' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '1.0' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '-1.0' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '+1.0' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '0.0' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '.0' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '1.234:' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '1.234%' );
// returns true

bool = RE_DECIMAL_NUMBER.test( '0' );
// returns false

bool = RE_DECIMAL_NUMBER.test( 'beep 0' );
// returns false

bool = RE_DECIMAL_NUMBER.test( '2:3' );
// returns false

bool = RE_DECIMAL_NUMBER.test( 'beep' );
// returns false

bool = RE_DECIMAL_NUMBER.test( '' );
// returns false

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Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2025. The Stdlib Authors.