Parsing a file into a hash

[joe2684]

I have got a file containing info abt node id and labels, which looks like this

-645    _1__46__1__46__1__46__145__45__RXN
-435    _3__45__OXOACYL__45__ACP__45__REDUCT__45__RXN
-1084    RXN__45__4262
-565    RXN__45__4264
-740    RXN__45__710
-1290    RXN__45__7698
-1017    LIPOXYGENASE__45__RXN
-198    RXN__45__1321
-1151    RXN__45__4121
-55    GIBBERELLIN__45__3__45__BETA__45__DIOXYGENASE__45__RXN
-1276    NARINGENIN__45__3__45__DIOXYGENASE__45__RXN
-653    RXN__45__113
-455    RXN__45__114
 

i have to read this file into a hash, for which i converted it first into an array, and then to hash, using a program like this

open (NODES, "node.txt") || die "File not found\n";
@nodearray=<NODES>;
%nodehash=@nodearray;
 

now i have got to take labels as input from the user, and return the node id. I have been trying the following code

# usr/bin/perl -w
 
$start_node = 'AT1G51570';
$end_node = 'AT5G1110';
 
open (NODES, "node.txt") || die "File not found\n";
@nodearray=<NODES>;
%nodehash=@nodearray;
 
while (($node_id,$label) = each %nodehash) {
    if ($nodehash{$label} = $start_node) {
        print $nodehash{$node_id};
    }
}
 

but nothing is working out. Please help me out on it. I am new to programming, and my deadline is just arriving. Please suggest something....

[KevinADC]

Please suggest something...

ask a question that we can understand so we can attempt to answer it.

[numberwhun]

but nothing is working out. Please help me out on it. I am new to programming, and my deadline is just arriving. Please suggest something....

Just taking a quick look, I am going to guess that this is not the entire data file since the $start_node value doesn't exist anywhere in there.

I must say that I agree with Kevin and need to clarify better what exactly you are asking and looking for. You say that the two fields in the file are node_id and label, in that order. Then the user enters a label, you are supposed to match it against the file and if a match occours, then print the node_id. From what I can see though, that is NOT what you are doing. You are comparing what the user would enter to a fixed value($start_node), if the user were even able to enter a value. Your script doesn't allow for the user input that you are mentioning.

I think that you really need to clean up this program and try to get it working. Heck, pick up a copy of Learning Perl as it will truely help you with the language and writing Perl code. If you still have problems after trying to meet your requirements, then be sure to repost, but please word the question better so we are able to assist you.

Regards,

Jeff