Perl confusion

[stamp1982]

Ask the user for a list of sequence lengths, separated by whitespace (Example: 100 123 45 …etc.). The sequence lengths will be stored in a string called $input. a. Split the String $input and create an array. b. Use the foreach loop to get the sum of all sequence lengths. c. Print the average. this is what I have now: but I don't get the space at the print command. use strict; use warnings; my $i = 0; my $input = ""; while ($i < 3) { chomp(my $num = <>); $input .= $num . "". $num; $i++; } print "Total input is $input\n"; my @nums = split(' ', $input); foreach (@nums) { my $sum += $_; } print my $sum / @nums . "\n"; exit;

[Ralesk]

Welcome to PerlMonks!

Please read How do I compose an effective node title?, How do I post a question effectively? and Markup in the Monastery for more effective posting.

That out of the way though, you’re best off consulting perldoc -f split about the split function (and play around with it, it’s fun), perldoc perlsyn about Foreach Loops and perldoc perlop about mathematical (and other) operators.

Have fun!

[stamp1982]

Ralesk, I would be able to perform for each loop, print average and split. My real confusion is how to obtain the sequence length separated by white space in perl and that is what I need clarification on. Thanks!

[kcott]

G'day stamp1982,

One of these might have what you're after:

• Perl and Bioinformatics
• HOWTOs - BioPerl

[5mi11er]

This isn't the place to get homework done for you. We expect you to try it on your own, and then when you're stuck with some specific problem, we'll typically help you through that one issue. There's lots of perl on the net, google around find something close, cobble it together to try to accomplish your task, and google through the simple issues. Then come back with code and ask a specific question about why it does something you didn't expect, or doesn't do what you did expect.

-Scott

[stamp1982]

Scot, Thanks for your message. I did not want a solution to the problem but a breakdown of what was expected in a beginners terms. I know to obtain user input I have to use STDIN but how to write that obtain that with the whitespace is where my confusion lies and I would appreciate some explanation. It is not my homework just practicing Perl for beginners. Please what does the sequence length mean? Thanks

[5mi11er]

I don't know what "sequence length" means. Googling, and noting from the chatterbox you were in the pharmaceutical industry, I would have to guess http://en.wikipedia.org/wiki/Simple_sequence_length_polymorphism is what you're looking at?

-Scott