Return the maximum positive and minimum negative product
if ( lowest < 0 && highest >= 0 ) { return ( [ Math . max ( highPos , lowNeg ) , Math . min ( highNeg , lowPos ) ] ) ; } else if ( lowest <= 0 && highest <= 0 ) { return ( [ lowNeg , lowPos ] ) ; } else if ( lowest >= 0 && highest >= 0 ) { return ( [ Math . max ( lowPos , highPos ) , Math . min ( lowNeg , highNeg ) ] ) ; } return ( [ 0 , 0 ] ) ; }