presto-main/src/main/java/io/prestosql/operator/scalar/MathFunctions.java/MathFunctions/exp
class MathFunctions:    @Description("Euler's number raised to the given power")
    @ScalarFunction
    @SqlType(StandardTypes.DOUBLE)
    public static double exp(@SqlType(StandardTypes.DOUBLE) double num)
    {
        return Math.exp(num);
    }