in reply to Re: optimize percentile counting in hash
in thread optimize percentile counting in hash

Thanks for trying to help me out. I really appreciate it :)

I was not using \<code\></code> may be that's y u had error. The code should work now. I HAVE TO FIND PERCENTILE AND NOT PERCENTAGE :( which makes it more difficult to execute in less time.

Eagerly waiting for reply, thanks again
  • Comment on Re^2: optimize percentile counting in hash

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Re^3: optimize percentile counting in hash
by ikegami (Patriarch) on Mar 21, 2008 at 01:56 UTC
    How about 
    use strict;
use warnings;

my @data = get_data(); # or however you get them

my %count;
foreach my $datum (@data) {
    ++$count{$datum};
}

my %percentile;
my $total = 0;
foreach my $datum (sort { $a <=> $b } keys %count) {
    $total += $count{$datum};
    $percentile{$datum} = $total / @data;
}

    [download]
[reply]
[d/l]

      its giving incorrect percentile values :( to find percentile rank of score x out of n scores:
      (number of scores below x)/n*100 = percentile rank
      need to sort the hash first, i used index value of the array to find number of scores below x. x is value of hash taken one by one and returning the percentile

[reply]
        oh, below, not below or equal. Just switch the order of the two statements in the last loop. I usually only do the *100 when it's time to print, but I added it for you. 
        use strict;
use warnings;

my @data = get_data(); # or however you get them

my %count;
foreach my $datum (@data) {
    ++$count{$datum};
}

my %percentile;
my $total = 0;
foreach my $datum (sort { $a <=> $b } keys %count) {
    $percentile{$datum} = $total / @data * 100;
    $total += $count{$datum};
}

        [download]
[reply]
[d/l]
Re^3: optimize percentile counting in hash
by apl (Monsignor) on Mar 21, 2008 at 02:24 UTC
    For future reference, if you modify your original post, you should also add a Revised: note, explaining the change. Otherwise it's confusing to the people new to the thread.
[reply]
      sorry, got logged out and posted msg as anonym.... the formula for percentile is given by me, sorry for confusion...... plz help
[reply]
      will keep that in mind, thanks :)
[reply]

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