101 LINQ samples: Custom sequence Operators

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• Combine

Combine

This sample calculates the dot product of two integer vectors. it uses a user-created sequence operator, combine, to calculate the dot product, passing it a Lambda function to multiply two arrays, element by element, and sum the result.

Public static class customsequenceoperators
{
Public static ienumerable combine (this ienumerable first, ienumerable second,
Func ){
Using (ienumerator e1 = first. getenumerator (), E2 = second. getenumerator ())
{
While (e1.movenext () & e2.movenext ()){
Yield return func (e1.current, e2.current );
}
}
}
}

Public void linq98 (){
Int [] vectora = {0, 2, 4, 5, 6 };
Int [] vectorb = {1, 3, 5, 7, 8 };

Int dotproduct = vectora. Combine (vectorb, (a, B) => a * B). sum ();

Console. writeline ("dot product: {0}", dotproduct );
}

result

Dot Product: 109