Cross Product of arrays using LINQ


Cross Product is usually a database operation on two tables similar to a Join operation with the only difference is that the cross product will yield all the possible combinations  between the two tables. Database Management Systems such as SQL Server and Oracle provided the cross product operation easily using the cross join keyword. The problem however in real life applications appears when we want to do cross product within the application logic. Suppose you have two arrays of numbers and you want to find out all the possible combinations of the two arrays together, then pick one of those combinations that meet your specific business needs. Fortunately, with the introduction of LINQ in the past few years, cross product has become as simple as writing any other naive query. Lets take a look at the example below: consider two arrays A and B having 4 values each:

        Dim A() As Integer = {1, 2, 3, 4}
        Dim b() As Integer = {5, 6, 7, 8}

Cross product is simply obtained using the following LINQ query followed by writing out the results to console:

        Dim crossProduct = From x In A, y In b Select x, y
        For Each i In crossProduct
            Console.WriteLine(i)
        Next

This will yield the following results:

About these ads

One Response to Cross Product of arrays using LINQ

  1. this can be a simple query, but is slow
    take care

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 62 other followers

%d bloggers like this: