in reply to Re^4: constructing a tree from csv file
in thread constructing a tree from csv file

Read perldata - Perl data types to learn on how to use hashes. See below on how I would implement it. 
#!/usr/bin/perl
use warnings;
use strict;

my %group = ('P.P'    => 'A',
             'P.P.E'  => 'B',
             'P.P.PL' => 'C',
             'P'      => 'D',
            );

<DATA>; # Skip header.

my %tree;
while (<DATA>) {
    chomp;
    my ($child, $parent, $relation) = split /,\t/;
    $relation =~ s/,$//;
    $tree{$child}{parent} = [$parent, $relation];
}

for my $node (keys %tree) {
    my @path      = $node;
    my @relations = ($tree{$node}{parent}[1]);
    my $parent    = $node;

    while ($parent = $tree{$parent}{parent}[0]) {
        push @path, $parent;
        push @relations, $tree{$parent}{parent}[1];
    }

    my $path_string = join '.', reverse grep defined, @relations;

    print "$node:\t";
    print join '<-', @path;
    print " = ", $path_string, ', ', $group{$path_string};
    print "\n";
}

__DATA__
child,  Parent, relation
M10,    Q,    P,
M143,    M10,    P,
M406,    M143,    PL,
M407,    M143,    PL,
M420,    M143,    E,
M421,    M143,    E,

[download]
لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

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Re^6: constructing a tree from csv file
by zing (Beadle) on Nov 11, 2013 at 03:53 UTC
    Thanks but Im getting this error :- 
    Use of uninitialized value in print at final.pl line 35, <DATA> line 7
+.
, ,3:   M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 35, <DATA> line 7
+.
, ,0:   M420<-M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 35, <DATA> line 7
+.
, L,:   M407<-M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 35, <DATA> line 7
+.
, 0:    M10<-Q = P,
Use of uninitialized value in print at final.pl line 35, <DATA> line 7
+.
, ,1:   M421<-M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 35, <DATA> line 7
+.
, L,:   M406<-M143<-M10<-Q = P,

    [download]
[reply]
[d/l]
      Did you use the [download] link to get the code? Tab characters are used in the DATA section, plain spaces would break the programme.
      لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
[reply]
[d/l]
        Ohh yeah. BTW I must say, I leant a lot by simply reading through your code. Thanks it was lucidly written.
[reply]
        Choroba I did it but again the same error- 
        Use of uninitialized value in print at final.pl line 71, <DATA> line 7
+.
, ,3:   M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 71, <DATA> line 7
+.
, ,0:   M420<-M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 71, <DATA> line 7
+.
, L,:   M407<-M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 71, <DATA> line 7
+.
, 0:    M10<-Q = P,
Use of uninitialized value in print at final.pl line 71, <DATA> line 7
+.
, ,1:   M421<-M143<-M10<-Q = P,
Use of uninitialized value in print at final.pl line 71, <DATA> line 7
+.
, L,:   M406<-M143<-M10<-Q = P,

        [download]
        LINE 71 being   print " = ", $path_string, ', ', $group{$path_string};
[reply]
[d/l]
[select]
        Choroba i modified your code for my requirements and now %group hash has 40 keys, and __DATA__ has 345 lines. The problem is that the code hangs and gets killed after sometime without any output. CPU usage going to 100%,system hang. Whereas if I reduce the __DATA__ lines to 300 lines only, then it runs . Why is it so. My system has 64Gigs ram, and hexacore.
[reply]
        Choroba the reason for uninitliazed error that Im getting is because my group hash doesnt have relations which are more than length 3. As you can see below. E.P.E.E is 4 relations. But thats alright as I dont want to have relations which are more than three. But could this also be the reaso n behind the program getting hanged when run on __DATA__ more than 300 lines:- 
        Use of uninitialized value in print at checking.pl line 71, <DATA> lin
+e 338.
M61:    M61<-M7<-M28<-M6<-Q = E.P.E.E,
Use of uninitialized value in print at checking.pl line 71, <DATA> lin
+e 338.
M196:   M196<-M53<-M7<-M28<-M6<-Q = E.P.E.Pl.E,

        [download]
[reply]
[d/l]

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