As halley indicated, an absolute Epsilon test doesn't work well for all kinds of data. What about fractional comparison? e.g,:

sub fromp {
    my ( $x, $y, $eps) = @_;
    ( abs( ($y - $x ) / ( $x || $y || return (1) ) ) < $eps );
}
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$eps should be the fractional closeness e.g. 0.000000001 would invoke a fractional threshold of a billionth.

The chain of ||s ensures that either the divisor is non-zero or division is prevented by returning 1 where both are 0 (therefore equal).