Perl Guru Forums: Perl Programming Help: Beginner: Problem

CGI/Perl Guide | Learning Center | Forums | Advertise | Login

Site Search: in


	MAIN INDEX	SEARCH POSTS	WHO'S ONLINE	LOG IN

Home: Perl Programming Help: Beginner:
Problem

yaroba
Novice

May 26, 2013, 12:00 PM

Post #1 of 8 (1060 views)

Problem	Can't Post

Hello,

I have a task that sounds this: You have real and natural numbers in .txt file and you have to put every element in between <> brackets. Can anyone help me?

g4143
Novice

May 26, 2013, 1:40 PM

Post #2 of 8 (1053 views)

Re: [yaroba] Problem [In reply to]	Can't Post

Can you give us an example of the text file?

yaroba
Novice

May 26, 2013, 1:55 PM

Post #3 of 8 (1050 views)

Re: [g4143] Problem [In reply to]	Can't Post

the .txt file should look like this : 23530-2-5

Laurent_R
Veteran / Moderator

May 26, 2013, 2:17 PM

Post #4 of 8 (1048 views)

Re: [yaroba] Problem [In reply to]	Can't Post

And how is your output supposed to look?

Code

<23530>-<2>-<5>

Code

<23530-2-5>

Adssuming the first answer, the following session under the Perl debugger gives a possible solution:

Code

  DB<14> $n = "23530-2-5"; 
 
  DB<15> $n =~ s/(\d+)/<$1>/g; 
 
  DB<16> print $n; 
<23530>-<2>-<5>

yaroba
Novice

May 26, 2013, 2:34 PM

Post #5 of 8 (1046 views)

Re: [Laurent_R] Problem [In reply to]	Can't Post

My bad, it should take one number after another and put it in the brackets. 2,3,5,3,0,-2,-5 should be converted to <2>, <3>, <5> and etc.

(This post was edited by yaroba on May 26, 2013, 2:58 PM)

BillKSmith
Veteran

May 26, 2013, 3:28 PM

Post #6 of 8 (1038 views)

Re: [yaroba] Problem [In reply to]	Can't Post

Code

use strict; 
use warnings; 
my $string = <DATA>; 
$string =~ s/([-+.\d]+)/<$1>/g; 
print $string; 
__DATA__ 
2,3,5,3,0,-2,-5

OUTPUT:

Code

<2>,<3>,<5>,<3>,<0>,<-2>,<-5>

Good Luck,
Bill

yaroba
Novice

May 26, 2013, 4:22 PM

Post #7 of 8 (1033 views)

Re: [BillKSmith] Problem [In reply to]	Can't Post

Thanks once again for your help :)

I have one more question, what is wrong with my code?

use strict;
use warnings;

my $string = '';

open my $FILE, '<', 'numbers.txt' or die;

while (<$FILE>) {
$string =~ s/([-+.\d]+)/<$1>/g;
print "$string\n";
}

BillKSmith
Veteran

May 26, 2013, 7:41 PM

Post #8 of 8 (1022 views)

Re: [yaroba] Problem [In reply to]	Can't Post

You are reading the file into $_, not $string.

Code

use strict; 
use warnings; 
open my $FILE, '<', 'numbers.txt' or die "Cannot open numbers.txt:$!"; 
#######while (<$FILE>) {  
while ( my $string = <$FILE> ) { 
    $string =~ s/([-+.\d]+)/<$1>/g; 
    print "$string\n"; 
}

Good Luck,
Bill

Search for (options)

Web Applications & Managed Hosting Powered by Gossamer Threads
Visit our Mailing List Archives