Matching floating point range using regular expression

Question

I need a regular expression, that matches within a range of floats.

For the range 12.33 - 13.41 I tried the following regex:

(12.[3-9][3-9]|13.?[0-4][0-1]?)\d{0,2}

but it doesn't match i.e. 12.41 or 13.39.

Is this possible with regular expressions?

Kind regards, bernie70

In what language are you trying to do this? Must be a much simpler solution for it? — putvande, Jun 26 '15 at 10:23
Do you just want to match the decimal part, or the complete number? — garyh, Jun 26 '15 at 10:25
I have already a solution in shell with an if construct, but I was experimenting with regexp and I want to know if it is possible. — bernie70, Jun 26 '15 at 11:55

score 0 · Answer 1 · answered Jun 27 '15 at 21:59

I don't know is it worth it, but it is possible. Try with:

(12.(3[3-9]|[4-9]\d))|(13(.([0-3]\d|4[01]))?)

it means:

12. -- starts with '12.',
3[3-9] -- 3 followed by digit from range 3 to 9 (33-39),
| -- OR
[4-9]\d -- digit from range 4 to 9 followed by any digit (40-99),
| -- OR
13 -- starts with '13'
. -- dot
[0-3]\d -- digit from range 0 to 3 followed by any digit,
| -- OR
4[01] -- 4 followed by 0 or 1,
? -- zero or one time

and (.([0-3]\d|4[01]))? is treated as a one group, to allow '13', but not '13.'

It will match numbers like: 12.33, 12.99, 13.41 ,13 ,12.41 ,13.39 ,etc. and will ignore: 12.32, 13.42, etc.

Your code didn't work because:

(12.[3-9][3-9]|13.?[0-4][0-1]?)\d{0,2}

[3-9][3-9] - allows only numbers from ranges (33-39,43-49,53-59,...),
[0-4][0-1] - allows only numbers (00,01,10,11,20,21,30,31,40,41),

so there is huge omitted range

score 0 · Answer 2 · answered Jun 29 '15 at 18:30

0

thank you for the tip.

I modified the regex a little bit to the following:

(12.(3[3-9]|[4-9])).|(13(.([0-3][0-8])).)|^(13.[0-3][9][0]*)$

So I can match the range I want.

answered Jun 29 '15 at 18:30

bernie70

17
1

score -1 · Answer 3 · answered Dec 01 '19 at 21:36

A straight forward way to match the float range 12.33 - 13.41 is :

12\.(?:3[3-9]|[4-9]\d)|13\.(?:[0-3]\d|4[01])

Expanded

   #  12.33  to  12.99
   12 \. 
   (?:
        3 [3-9] 
     |  [4-9] \d 
   )
|  
   #  13.00  to  13.41
   13 \. 
   (?:
        [0-3] \d 
     |  4 [01] 
   )

Matching floating point range using regular expression

3 Answers3