Re: Gawk match() and numbers in scientific notation

On 5/7/2008 1:16 PM, schuler.steffen@[EMAIL PROTECTED]
 wrote:
> On May 7, 8:03 pm, Ed Morton <mor...@[EMAIL PROTECTED]
> wrote:
> 
>>On 5/7/2008 12:50 PM, Hermann Peifer wrote:
>>
>>
>>
>>
>>>Ed Morton wrote:
>>
>>>>On 5/6/2008 6:16 AM, Hermann Peifer wrote:
>>>
>>>>>Hi,
>>>>
>>>>>I am somehwat puzzled with match() results for numbers in scientific
>>>>>notation. See below.
>>>>
>>>>>$ cat testdata
>>>>>100
>>>>>100e-3
>>>>>100E3
>>>>
>>>>>I am wondering what kind of uppercase character is matched in record
>>>>>2:
>>>>
>>>>>$ gawk '{print $1,match($1,/[A-Z]/)}' testdata
>>>>
>>>>There may not be an uppercase character matching. [A-Z] represents the
list of
>>>>characters in between the character A and the character Z in your
locale - that
>>>>does NOT mean it has to be upper case characters. For example, your
locale might
>>>>consider characters ordered as:
>>>
>>>>       aAbBcCdDeEfF....zZ
>>>
>>>You are right: in my locale en_GB.UTF-8, [A-Z] matches all upper and
>>>lower case letters (including accented letters), except lower case a.
In
>>>return [a-z] matches all upper/lower case letters, except upper case Z.
>>
>>>>so "e" would sit between "A" and "Z". That's why you should use
character
>>>>classes instead of specific ranges, e.g.:
>>>
>>>>       gawk '{print $1,match($1,/[[:upper:]]/)}' testdata
>>>
>>>I will do so. Thanks, Hermann
>>
>>As the other part of this thread continues over at comp.unix.shell, I
came up
>>with this script which you can run to see which characters are contained
in
>>which character lists (REs actually):
>>
>>$ cat rechars.awk
>># Prints every character that matches a given RE.
>># Originally created to print all characters in a given character list.
>>#
>># usage:
>>#    LC_ALL=C awk -v re="[a-z]" -f rechars.awk
>>#    LC_ALL=en_GB awk -v re="[a-z]" -f rechars.awk
>>#    awk -v re="[[:upper:]]" -f rechars.awk
>>#
>>BEGIN{
>>    for (i=0;i<=1000;i++)
>>        chars[sprintf("%c",i)]
>>    for (c in chars)
>>        if (c ~ re)
>>            s=s c
>>    print re"="s}
>>
>>$ awk -v re="[A-Z]" -f rechars.awk
>>[A-Z]=ABCDEFGHIJKLMNOPQRSTUVWXYZ
>>
>>so you can play with that if you're curious about which characters match
in
>>specific locales...
>>
>>        Ed.
> 
> 
> Why is LC_COLLATE instead of LC_ALL in the above case not enough?

It may be enough, but LC_ALL works for this and less typing.

	Ed.