.sh check for numeric content

[Carl Johnson]

Carl Johnson <carlj at peak.org> writes:

> vogelke+unix at pobox.com (Karl Vogel) writes:
>
>>>> On Thu, 24 Jun 2010 09:24:39 +0800, 
>>>> Aiza <aiza21 at comclark.com> said:
>>
>> A> Receiving a variable from the command line that is suppose to contain
>> A> numeric values.  How do I code a test to verify the content is numeric?
>>
>>    The script below will work with the Bourne or Korn shell.
>>    Results for "0 1 12 1234 .12 1.234 12.3 1a a1":
>>
>>      0 is numeric
>>      1 is numeric
>>      12 is numeric
>>      1234 is numeric
>>      .12 is numeric
>>      1.234 is numeric
>>      12.3 is numeric
>>      1a is NOT numeric
>>      a1 is NOT numeric
>
> You might want to try testing "123..45".
> I tried changing:
>>    if expr "$arg" : "[0-9]*[\.0-9]*$" > /dev/null
> to:
>     if expr "$arg" : "[0-9]*\.*[0-9]*$" > /dev/null
> but it still claims that it is numeric, so *I* must be missing
> something.

I just realized that I had a stupid mistake there and should have
used:  
     if expr "$arg" : "[0-9]*\.[0-9]*$" > /dev/null

-- 
Carl Johnson		carlj at peak.org