Gossamer Forum: General: Perl Programming: Replace digit at the end of a string?

Nov 19, 2003, 10:31 AM

Andy

Veteran / Moderator (18441 posts)

Nov 19, 2003, 10:31 AM

Post #1 of 11

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Replace digit at the end of a string?

Hi. I have a string, like;

Code:
      $_ = 'Universities Worldwide Search Argentina2.htm'; 

       $_ =~ s/Universities Worldwide Search //; 
       $_ =~ s/\.htm|\.html//; 
$_ =~ s/\d$//; 

The part in red just doesn't seem to be doing what its supposed to. Anyone got any ideas on how I can remove the digit from the end? (its not on the end of all the array values).

TIA

Andy (mod)
andy@ultranerds.co.uk

Nov 19, 2003, 12:03 PM

Chaz

Enthusiast (819 posts)

Nov 19, 2003, 12:03 PM

Post #2 of 11

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Re: [Andy] Replace digit at the end of a string? In reply to

Hi Andy,

That works for me:

Code:
[14:59][piper@galaxy:~]$ perl -e ' 
my $string = "Universities Worldwide Search Argentina2.htm"; 
$string =~ s/Universities Worldwide Search //; 
$string =~ s/\.htm|\.html//; 
$string =~ s/\d$//; 
print "\n$string\n";'    

Argentina 
[14:59][piper@galaxy:~]$

Do you have new lines or other characters hiding at the end of the string maybe?

~Charlie

Nov 20, 2003, 12:10 AM

Andy

Veteran / Moderator (18441 posts)

Nov 20, 2003, 12:10 AM

Post #3 of 11

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Re: [Chaz] Replace digit at the end of a string? In reply to

Yeah, seem a bit weird. Because the variables don't have any other digits in them, all I did was use a generic replace of all digits.

Cheers

Andy (mod)
andy@ultranerds.co.uk

Nov 20, 2003, 6:37 AM

Crolguvar

Novice (26 posts)

Nov 20, 2003, 6:37 AM

Post #4 of 11

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Re: [Andy] Replace digit at the end of a string? In reply to

Hey Andy, I take it all the values of $_ will contain "Universities Worldwide Search ", right?

Assuming that, if all you want to do is get the name of the country without that string and drop any possible numbers after it and the two possible extensions (.htm and .html), then this expression should do the trick:

my $string = 'Universities Worldwide Search Argentina2.htm';
$string =~ m/Universities Worldwide Search ([^0-9]*)\d*\.html?$/;
print $1;

Basically: match the part of the string following "...Search " which does not contain numbers, followed by zero or more numbers, followed by ".htm" followed by zero or one "l" and start matching at the end of the string.

Let me know if that works for you.

Last edited by:

Crolguvar: Nov 20, 2003, 6:39 AM

Nov 20, 2003, 6:46 AM

GClemmons

User / Moderator (314 posts)

Nov 20, 2003, 6:46 AM

Post #5 of 11

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Re: [Andy] Replace digit at the end of a string? In reply to

print $1 if s/^.*\s+([^\d]+).*$//;

-g

s/(\d{2})/chr($1)/ge + print if $_ = '8284703280698276687967';

Nov 20, 2003, 6:47 AM

Andy

Veteran / Moderator (18441 posts)

Nov 20, 2003, 6:47 AM

Post #6 of 11

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Re: [Crolguvar] Replace digit at the end of a string? In reply to

Thanks, but the job I was using this in has already been completed. It was a quick script to go through a list of files, and grab a list of URL's from it. Thanks for taking the time to reply though.

Cheers

Andy (mod)
andy@ultranerds.co.uk

Nov 20, 2003, 6:51 AM

Andy

Veteran / Moderator (18441 posts)

Nov 20, 2003, 6:51 AM

Post #7 of 11

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Re: [GClemmons] Replace digit at the end of a string? In reply to

In Reply To:

print $1 if s/^.*\s+([^\d]+).*$//;

-g

Show off :)

Andy (mod)
andy@ultranerds.co.uk

Nov 20, 2003, 6:53 AM

GClemmons

User / Moderator (314 posts)

Nov 20, 2003, 6:53 AM

Post #8 of 11

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Re: [Andy] Replace digit at the end of a string? In reply to

Me? Never ;)

-g

s/(\d{2})/chr($1)/ge + print if $_ = '8284703280698276687967';

Nov 20, 2003, 9:35 AM

Recall

Novice (22 posts)

Nov 20, 2003, 9:35 AM

Post #9 of 11

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Re: [Andy] Replace digit at the end of a string? In reply to

FWIW, when you are matching or substituting using $_ then you can omit it from the code, for example:

Code:

if ($_ =~ /abc/) {

...equates to:

Code:

if (/abc/) {

Regarding the actual scenario you faced, performing a substitution actually modifies the variable, however if you only wanted to get the matching text, something like this may have worked....

Code:

my ($match) = $_ =~ /(\w+)\d+\.html?$/;

Nov 20, 2003, 9:39 AM

Andy

Veteran / Moderator (18441 posts)

Nov 20, 2003, 9:39 AM

Post #10 of 11

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Re: [Recall] Replace digit at the end of a string? In reply to

Thanks for the reply. Wouldn't it have been this though?

Code:
my ($match) = $_ =~ /(\w+)\d+(\.html|\.htm)?$/;

The extensions vary between .html and .htm.

Cheers

Andy (mod)
andy@ultranerds.co.uk

Nov 20, 2003, 9:42 AM

Recall

Novice (22 posts)

Nov 20, 2003, 9:42 AM

Post #11 of 11

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Re: [Andy] Replace digit at the end of a string? In reply to

Notice I have a "?" after the .html ...that means the "l" is optional so it will match .htm or .html