Peter Lemus wrote:
> I need to read a huge two column file; I only need the
> data from the second column; I need to asign it a
> variable to that column, for example $FILE, how do go
> about doing this; I appreciate your help.
>
> the file looks like this
>
> md tony
> md ariba
> md arpa
in the spirit of TMTOWTDI...
here's a "verbose" solution:
#!/usr/bin/perl -w
# two-column <filename>
use strict;
while (<>) {
# split line on whitespace
my @words = split; # same as: my @words = split / /; (with
leading nulls discarded)
# same as: my @words = split / /, $_;
# same as: my @words = split /\s+/, $_;
# assign second word to $FILE
my $FILE = $words[1];
# do whatever with $FILE
print "i got '$FILE'\n";
}
usage: two-column file.txt
the -n option will (basically) wrap a "while (<>) { }"
around the body of the script, to save some space:
#!/usr/bin/perl -wn
use strict;
my @words = split;
my $FILE = $words[1];
print "i got '$FILE'\n";
you can remove @words to get:
#!/usr/bin/perl -wn
use strict;
my $FILE = (split)[1];
print "i got '$FILE'\n";
you can autosplit (to the @F array) on whitespace with -a:
#!/usr/bin/perl -wan
use strict;
my $FILE = $F[1];
print "i got '$FILE'\n";
and here's a one-liner you can run at the command line:
$ perl -lane 'my $FILE = $F[1]; print "i got $FILE"' file.txt
> I will have a loop going over and reassingn the next
> name to the same variable.
i'm having trouble parsing this.
--
Steve Lane <[EMAIL PROTECTED]>
