JavaScript / ECMAScript

Scientific Notation in JS

Matches numbers in scientific/exponential notation (e.g., 1.5e10).

Try it in the JS tester →

Pattern

regexJS
^-?\d+(\.\d+)?[eE][+-]?\d+$

JavaScript / ECMAScript code

jsJavaScript
const re = new RegExp("^-?\\d+(\\.\\d+)?[eE][+-]?\\d+$", "");
const input = "1.5e10";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));

Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).

How the pattern works

`^-?\d+(\.\d+)?` matches a signed decimal. `[eE]` allows either exponent marker. `[+-]?\d+$` matches the signed exponent digits.

Examples

Input

1.5e10

Matches

  • 1.5e10

Input

-2.7E-5

Matches

  • -2.7E-5

Input

3.14

No match

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Same pattern, other engines

Python (re)

Supported

See how this pattern looks (and behaves) in Python's stdlib `re` module.

Go (RE2)

Supported

See how this pattern looks (and behaves) in Go's `regexp` package (RE2 engine).

← Back to Scientific Notation overview (all engines)