tlynch001 has asked for the wisdom of the Perl Monks concerning the following question:

Please help me with this seemingly simple problem
I have a txt file containing data in this format:
http://csdweb.unf.edu/access/htdocs/student.htm, , , 5, 0, 0, 0
I want to read each line into an array, making a multidimensional array, so I did this: 

#! /usr/bin/perl -w
# Open our datafile
open(INPUT, '< graduate.output.txt')
   or die "Couldn't open the file for reading\n";
# Declare main array
@MainArray = ();
# build a data structure
@url_info = <[INPUT]>;
while(1){
   print "Pick a number: ";
   $index = <STDIN>;
   if($index eq 'Q'){
      last;
   }
   print "Link: $url_info[$index][0]\n";
}

[download]

But the print only displays the work Link:
Of course, this is rigged to only print the URL. But I'm still troubleshooting.
And why doesn't my loop quit if I type a Q?
Thank you very much!
-tl

Replies are listed 'Best First'.
Re: Array question II
by japhy (Canon) on Mar 14, 2001 at 20:21 UTC
    You should not have <[INPUT]>, but rather <INPUT>.

    And if you checked to see what $index held, you'd see that it has a newline at the end of it. Try: 

    chomp($index = <STDIN>);
if ($index eq 'Q') { ... }

    [download]


    japhy -- Perl and Regex Hacker
[reply]
[d/l]
      But that gives me an array of elements, I was hoping that each "string" would be it's own list, giving me a list of list.

      Thanks,

      -tl

[reply]

        In that case, you need to split each record as you read it from the file and push a reference to the resulting array onto your main array.

        Oh, and you really should start using use strict in your code. It'll find a lot of subtle bugs.

        --
        <http://www.dave.org.uk>

        "Perl makes the fun jobs fun
        and the boring jobs bearable" - me

[reply]
Re: Array question II
by buckaduck (Chaplain) on Mar 14, 2001 at 20:56 UTC
    It's also worth pointing out that you haven't created a multidimensional array. Therefore, $url_info[$index][0] won't give you what you want.

    While we're at it, go ahead and print out the error code if the open() fails.

    Try reading the INPUT filehandle like this: 

    open(INPUT, '< graduate.output.txt')
     or die "Couldn't open the file for reading: $!";

while(<INPUT>) {
  chomp;
  my $@a = split /,/;
  push(@url_info, \@a);
}

close(INPUT);

    [download]
    buckaduck
[reply]
[d/l]
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