Question

How to convert the below code

double sumxy = 0;

for (int i = 0; i < x.Count; i++)
{sumxy = sumxy + (x[i] * y[i]);}

by using lambda

I am using C#3.0. x and y are list of double numbers

Thanks

Answer 1

If you’re using .NET 4, you could use the Zip operator:

double sumxy = x.Zip(y, (a, b) => a * b).Sum();

Or in .NET 3.5:

double sumxy = x.Select((value, index) => value * y[index]).Sum();