gistfile1.cs

            double[] src = new double[] {1.0,2.0,3.0,4.0};
            double[] val = new double[]{0.0,1.0,2.0,3.0};
            double[] dest = src.Select(BitConverter.DoubleToInt64Bits).
                                Zip(val.Select(BitConverter.DoubleToInt64Bits), 
                                (a, b) => BitConverter.Int64BitsToDouble(a & b)).ToArray();

gistfile2.cs

    class Foo
    {
        public static T Max<T>(T a, T b)
        {
            return b;
        }
    }