Regex with integer and decimals and dot and sign

Question

I am trying to validate a string with following allowed conditions

string can be signed or unsigned numbers with dot(.). for example

10 or .3 or 1. or 1.1 or +5 or -5 or +.3 or -1. etc

below link is almost a close answer but fails on "+.3" Regular Expression for whole numbers and integers?

"[+-]?(?<!\.)\b[0-9]+\b(?!\.[0-9])"

Please stick to one language tag; using 3 is tantamount to spamming disparate communities. — Martijn Pieters, Apr 09 '14 at 10:54
Looks like I got the solution [+-]?\d+(\.\d*)?|\.\d|[+-]?(\.\d) — user3514797, Apr 09 '14 at 10:57
related: [Extract float/double value](http://stackoverflow.com/q/385558/4279) — jfs, Apr 09 '14 at 11:20

Sufian Latif · Answer 1 · 2014-04-09T11:29:00.443

0

One solution may be:

[+-]?(((\d+\.?)|(\.?\d+))\d*)

Here [+-]? checks for the optional sign at the beginning, (\d+\.?) and (\.?\d+) will catch digit followed by . or . followed by digits (and covers the cases that contain a .), and finally \d* takes care of the trailing digits, if there is any.

edited Apr 09 '14 at 11:29

answered Apr 09 '14 at 11:21

Sufian Latif

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d_z · Accepted Answer · 2014-04-09T11:46:14.300

-1

if you want to exclude strings like 000000.12 this would work I beleive [+-]?(0|[1-9]\d*)?(\.[0-9]+)?

edited Apr 09 '14 at 11:46

answered Apr 09 '14 at 11:04

d_z

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This regex will capture only `+`, only `-` or even an empty string. – Sufian Latif Apr 09 '14 at 11:57
@0605002 Thanks, you are right. Here is the fixed version `[+-]?(((0|[1-9]\d*)(\.\d*)?)|(\.\d+))` – d_z Apr 09 '14 at 13:02
This one captures `'-0'` from `'-0123.45'`. – Sufian Latif Apr 09 '14 at 16:24

Regex with integer and decimals and dot and sign

2 Answers2