sub my_mod { my ( $a, $b ) = @_; my $div = $a / $b; return $a - int( $div ) * $b; } print my_mod( 4, 1.5 ), "\n"; # 1 print my_mod( 4, 0.5 ), "\n"; # 0 print my_mod( 4, 0.7 ), "\n"; # 0.5