Re: filling in the zeros...please help

[jaredor]

If you can hold everything in memory, this should come close to doing what you want. It has the following assumptions/behviors:

• Each row has the same number of whitespace delimited fields (columns).
• Zeroes starting a column or ending a column are meant to be zeroes after patching.

#!/usr/bin/env perl

use Modern::Perl;
use Data::Dump qw(pp);

my %cols;
my @patch_cols = qw(2 3);

while (<DATA>) {
    my @row = split;
    push @{$cols{$_}}, $row[$_] for (0..$#row);
}

for my $col (@patch_cols) {
    my @fwd = @{$cols{$col}};
    my @bwd = reverse @fwd;
    for my $i (1..$#fwd) {
        $fwd[$i] = $fwd[$i-1] if $fwd[$i] == 0;
        $bwd[$i] = $bwd[$i-1] if $bwd[$i] == 0;
    }
    @bwd = reverse @bwd;
    $fwd[$_] == $bwd[$_] and $cols{$col}->[$_] = $fwd[$_] for (0..$#fw
+d);
}

say pp(\%cols);
say pp(\@patch_cols);

__DATA__
1    100    1    2
101    200    1    2
201    300    1    0
301    400    1    0
401    500    0    2
501    600    0    2
601    700    0    0
701    800    1    1
801    900    1    2

Produces:

{
  "0" => [1, 101, 201, 301, 401, 501, 601, 701, 801],
  "1" => [100, 200, 300, 400, 500, 600, 700, 800, 900],
  "2" => [1, 1, 1, 1, 1, 1, 1, 1, 1],
  "3" => [2, 2, 2, 2, 2, 2, 0, 1, 2],
}
[2, 3]

[david_lyon]

Thanks jaredor very much it helped me a lot.


Do you know or anyone else know how to output the results in the same format at the input file ie tab delimited?

Thanks so much again
Dave

[jaredor]

Dave,

You have a hash of arrays; each array is the same length; each array represents a column; the hash key for an array is the number of the column (starting at zero) that it represents. Because of this nice regularity, you can use a for loop like above and print out each row (starting from 0) with a simple print statement. (Actually, it would be even simpler to have an array of arrays, but not that much simpler for it to be worthwhile for me to go back and edit code from my mobile device.)

And since I'm not using a "real" keyboard at the moment, I'm not going to write out any lines of code. However, I probably shouldn't: You need to have the perl skills to do this relatively simple task. If you can't do this, then you probably don't understand what the above code is doing. You need to understand that first.