What you need is a set of comparison functions that implement a "close enough" concept of equality, like moritz says above, and then use them consistently.

Here are a few routines I wrote ages ago. Modify the cmp_eq routine for your desired level of "close enough". 

#-------------------------------------------
# Greater Than ($a > $b)
#-------------------------------------------
sub cmp_gt
{
    my ($a, $b) = @_;
    return 1 if !cmp_eq($a,$b) && $a > $b;
    return 0;
}

#-------------------------------------------
# Less Than ($a < $b)
#-------------------------------------------
sub cmp_lt
{
    my ($a, $b) = @_;
    return 1 if !cmp_eq($a,$b) && $a < $b;
    return 0;
}

#-------------------------------------------
# Equal To ($a == $b)
#-------------------------------------------
sub cmp_eq
{
    my ($a, $b) = @_;

    return 1 if $a == $b;       # Short circuit if rounding is not a p
+roblem

    # One-Thousandth of 1 percent of bigger value magnitude. (10^-5)
    my ($ma,$mb) = (abs($a),abs($b));
    my $piddly = 0.00001 * ($ma > $mb ? $ma : $mb);

    return 1 if abs($a-$b) <= $piddly;
    return 0;
}

#-------------------------------------------
# Greater Than or Equal To ($a >= $b)
#-------------------------------------------
sub cmp_gteq
{
    my ($a, $b) = @_;
    return cmp_gt($a,$b) || cmp_eq($a,$b);
}

#-------------------------------------------
# Less Than or Equal To ($a <= $b)
#-------------------------------------------
sub cmp_lteq
{
    my ($a, $b) = @_;
    return cmp_lt($a,$b) || cmp_eq($a,$b);
}

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In reply to Re: eq vs == by gmargo
in thread eq vs == by spikeheap

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