A little regexp help for a newbie

Sorry this is such an absurdly simple question, but I can’t find the
answer
after some googling, probably just me not knowing how to look.

Anyway, I have a simple string in the format 1a2+3 and want to basically
take out the non-number bits and put the numbers into an array.
It also has to match more than single-digit numbers. The rest is simple
enough, but I’m just really new to regex and can’t make it work.
Anyone feel like helping me out a little, or at least pointing me in the
right direction? Thanks.

On 8/4/06, RJ Melton [email protected] wrote:

Anyway, I have a simple string in the format 1a2+3 and want to basically
take out the non-number bits and put the numbers into an array.
It also has to match more than single-digit numbers.

I’m pretty sure this is non-optimal, but you could use String.split:

“1a23+4-123”.split(/[^\d]/)

the argument to split is a regex that matches anything that’s not a
digit ( \d is a digit; [^\d] is anything but that). split uses that
argument to decide where to split the string up.

;D

I tried that and it works fine, optimal or not. Thanks. :slight_smile:

What about “1a2+b”.scan(/\d+) ?
It returns the numbers as array.

RJ Melton schrieb:

On 8/4/06, Robert R. [email protected] wrote:

What about “1a2+b”.scan(/\d+) ?
It returns the numbers as array.

Muuuuch better!

On 8/4/06, Daniel B. [email protected] wrote:

http://danielbaird.com (TiddlyW;nks! :: Whiteboard Koala :: Blog ::
Things That Suck)

Will this pick up negative numbers or floats?

On 8/4/06, Robert R. [email protected] wrote:

What about “1a2+b”.scan(/\d+) ?
It returns the numbers as array.

Will this pick up negative numbers or floats?

Nope, only plain digits. if you want other stuff, you need to add it
to the regex.
/\d+/ …is just digits
/[±]?\d+/ …optional + or -
/[±]?\d+.?\d*/ …optional + or -, and optional .

untested… (sorry, too lazy to test :slight_smile:

p “-1.2 56 0.443 4.22E-12 000555”.scan(
/(?:[±])?[0-9]+(?:[,.][0-9]+)?(?:E[±][1-9][0-9]*)?/ )
#=> ["-1.2", “56”, “0.443”, “4.22E-12”, “000555”]

This looks okay for most purposes, in my opinion. :slight_smile:
You can google for “real number regex” et cetera…

Daniel B. schrieb:

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