Convert two arrays to a new one using LINQ

Question

I have two double[] X and double[] Y.
I want to create a new array Z, where each Zi = Xi * Yi

I wonder if it's possible to do with LINQ?
(I'm learning LINQ now; of course I can use plain for).

Answer 1

It's possible at 4.0, using Zip (that's the definition of zip - combining elements on the same position):

double[] Z = X.Zip(Y, (x, y) => x * y).ToArray();

On 3.5 you can use MoreLinq, which has a custom Zip extension method.

Answer 2

If you don't want to use a 3rd party lib or .NET 4.0, you could use 'Select'

double[] z = x.Select((d, i) => d * y[i]).ToArray();

'i' is the index of element 'd' for the current iteration and it's used here to retrieve the accordant element from y.