Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl Monk, Perl Meditation

Re: Faulty Control Structures?

by Errto (Vicar)
on Jan 28, 2008 at 20:33 UTC ( #664769=note: print w/replies, xml ) Need Help??

in reply to Faulty Control Structures?

I tried running the program on the data you provided but it exited instantly and printed no output in output.txt so I assume that data is not representative. I don't exactly understand what the code is doing but I don't see anything that could cause an infinite loop. I see two things that make me suspicious: 1) your range data is all numbers but you're using the character-operators lt and eq to compare them, and 2) these lines:

# look to see if the windows don't overlap if ($test lt $window[0]) {return 0;} # look to see if the windows don't overlap elsif ($test2 lt $probe[0]) {return 0;}
are inside a loop in which the iterator variable is $value1, yet they don't consider that value.

Update: Second thought - the second part of the code seems, if I understand it, to be designed to take two ranges of numbers and see if they overlap. To do so, it actually expands the ranges into lists and compares them one-by-one. This becomes, in the worst case, an N^2 calculation for what should be a constant operation:

sub range_overlap { my ($start1, $end1, $start2, $end2); return ($end1 >= $start2 || $start1 <= $end2) && ($end2 >= $start1 || $start2 <= $end1); }
untested but it should be about right.

Replies are listed 'Best First'.
Re^2: Faulty Control Structures?
by bioinformatics (Friar) on Jan 28, 2008 at 20:46 UTC
    Mmmm... The data won't match up your right. I can adjust the window values and chromosome numbers to match up so that you do get output however. I just threw up data to illustrate.

Log In?

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://664769]
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others surveying the Monastery: (6)
As of 2022-01-27 12:47 GMT
Find Nodes?
    Voting Booth?
    In 2022, my preferred method to securely store passwords is:

    Results (70 votes). Check out past polls.