public static RatNum add(RatNum x, RatNum y, int k)
{
IntNum x_num = x.numerator();
IntNum x_den = x.denominator();
IntNum y_num = y.numerator();
IntNum y_den = y.denominator();
if (IntNum.equals(x_den, y_den))
{
return(RatNum.make(IntNum.add(x_num, y_num, k), x_den));
}
return(RatNum.make(IntNum.add(IntNum.times(y_den, x_num),
IntNum.times(y_num, x_den), k),
IntNum.times(x_den, y_den)));
}
/** Convert rational to (rounded) integer, after multiplying by 10**k. */
public static IntNum toScaledInt(RatNum r, int k)
{
if (k != 0)
{
IntNum power = IntNum.power(IntNum.ten(), k < 0 ? -k : k);
IntNum num = r.numerator();
IntNum den = r.denominator();
if (k >= 0)
{
num = IntNum.times(num, power);
}
else
{
den = IntNum.times(den, power);
}
r = RatNum.make(num, den);
}
return(r.toExactInt(ROUND));
}
public static RatNum divide(RatNum x, RatNum y)
{
return(RatNum.make(IntNum.times(x.numerator(), y.denominator()),
IntNum.times(x.denominator(), y.numerator())));
}