I got an uninitialized variable error the way you had it so I added the foreach bit here, & also changed the round to int(). I got your idea:

sub is_approximately_an_integer { foreach my $x ( @zeros ) { $x = shift; my $eps = 0.0001; return abs( $x-int($x) ) < $eps; } }

It seems to work ok like that. I guess next is to use the subroutine with $_ inside grep somehow?

my @wants = grep {  } values %haystack;

In reply to Re^4: question about what to grep(?) by crunch_this!
in thread question about what to grep(?) by crunch_this!

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