perl question

cmontr · 11-26-2008, 08:40 AM

hi guys;

could anyone tell how to remove anything after comma in each line using perl (Assuming a large file in Unix)

Text lineslooks like:

7345_v,8042404....
7346_v,8042405....
7347_v,8042406....
7348_v,8042407....
.
.
.
.
etc

thanks much

Telemachos · 11-26-2008, 09:17 AM

You could do this from the command-line with Perl as well, but here's a small script:

Code:

#!/usr/bin/perl
use strict;
use warnings;

#$^I = '.bak';

while (<>) {
  s/,.*//;
  print;
}

That replaces [the comma and everything after it] with nothing. (If you want to keep the comma, use s/,.*/,/ instead of what I have above.) Save this as, say, edit and then run it as perl edit file_name. If the output looks sane, then uncomment the line #$^I = '.bak' and run it again. Once you uncomment that line, the file will actually be changed and, for no charge, Perl will make a backup as file_name.bak. That way if you did something very wrong, you have a backup. Edit - now that I think of it, can I get credit for your homework?

cmontr · 11-26-2008, 09:31 AM

This was runnnig awesome - thank you so much ...

Quote:

Originally Posted by Telemachos

You could do this from the command-line with Perl as well, but here's a small script:

Code:

#!/usr/bin/perl
use strict;
use warnings;

#$^I = '.bak';

while (<>) {
  s/,.*//;
  print;
}

That replaces [the comma and everything after it] with nothing. (If you want to keep the comma, use s/,.*/,/ instead of what I have above.) Save this as, say, edit and then run it as perl edit file_name. If the output looks sane, then uncomment the line #$^I = '.bak' and run it again. Once you uncomment that line, the file will actually be changed and, for no charge, Perl will make a backup as file_name.bak. That way if you did something very wrong, you have a backup. Edit - now that I think of it, can I get credit for your homework?