use List::UtilsBy qw(max_by);

my @list=(0.03,0.04,0.01);

my $max=max_by {$_} @list;

print "Maximum of ",join(',',@list)," is $max\n";
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Yes, you're of course right. By stating that 'you need to go through list' I meant that general algorythm goes through list at least once and this is a must. What you will use for that task - List::Utils or grep or your own cycle - isn't important in this context.

And of course I can provide some code snippets, but I feel that this would be a bad idea for OP who doesn't show us a line of his own.

well my own code was like this.

#!/usr/bin/perl -w
use strict;
use warnings; 
my @data=<>;

foreach (@data)
{
 my @row=split(/\t/, $_);
 my $otuhead=shift(@row);
 my $logic=1;
   foreach (@row)
   {
   if ($_>=0.01){$logic++;}
   }  
 if ($logic!=1){print "$otuhead @row";}
 $otuhead=();
}
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And yes I am acutely aware that the basic algorithm for finding out max, min etc. from a list has actually go through the list. I was just looking for utilities, commands, or whatnot that can make it well ... look nice would probably be the best explanation. Something that does not need extra curly brackets and extra declared variables. Extra space and hmm more general eyestrain. The question was more motivated by general curiosity than an actual need for this current problem. Which I have already solved (probably quite horribly as people soon will point out I guess :D)

edit: in code I shift off the first element -because it is a header and therefore not numerical.