Is there a good LINQ way to do a cartesian product?

by

If I understand the question, you want the Cartesian Product of n sets of puppies.

It is easy to get the Cartesian Product if you know at compile time how many sets there are:

from p1 in dog1.Puppies
from p2 in dog2.Puppies
from p3 in dog3.Puppies
select new {p1, p2, p3};

Suppose dog1 has puppies p11, p12, dog2 has puppy p21, and dog3 has puppies p31, p32. This gives you

{p11, p21, p31},
{p11, p21, p32},
{p12, p21, p31},
{p12, p21, p32}

Where each row is an anonymous type. If you do not know at compile time how many sets there are, you can do that with slightly more work. See my article on the subject:

http://ericlippert.com/2010/06/28/computing-a-cartesian-product-with-linq/

and this StackOverflow question:

Generating all Possible Combinations

Once you have the method CartesianProduct<T> then you can say

CartesianProduct(from dog in person.Dogs select dog.Puppies)

to get

{p11, p21, p31},
{p11, p21, p32},
{p12, p21, p31},
{p12, p21, p32}

Where each row is a sequence of puppies.

Make sense?

More Related Contents:

  1. How to make LINQ execute a (SQL) LIKE range search
  2. How do I update a value in C# and SQL Server? [closed]
  3. Search SQL by date ASP.NET
  4. Sql: Incorrect syntax near ‘(‘ [closed]
  5. how to get date difference between two dates using DateDiff Excluding the weekends [duplicate]
  6. LINQ to Entities does not recognize the method ‘System.String ToString()’ method, and this method cannot be translated into a store expression
  7. Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints
  8. linq case statement
  9. Combination of List
  10. Equivalent of SQL ISNULL in LINQ?
  11. DropdownList DataSource
  12. Distinct in Linq based on only one field of the table
  13. Wildcard search for LINQ
  14. Get an IDataReader from a typed List
  15. Dynamically cross-join multiple different-size collections together in Linq (C#)
  16. Find all child controls of specific type using Enumerable.OfType() or LINQ
  17. Join and Include in Entity Framework
  18. ASP.NET ODBC Query with parameters
  19. What is passing parameters to SQL and why do I need it?
  20. The data source does not support server-side data paging
  21. Will using LINQ to SQL help prevent SQL injection
  22. Calling a SQL User-defined function in a LINQ query
  23. Index (zero based) must be greater than or equal to zero
  24. Issues Doing a String Comparison in LINQ
  25. no overload for method “ToString” takes 1 arguments
  26. Select multiple fields group by and sum
  27. How to convert DataTable to class Object?
  28. Database Error: There is no row at position 0
  29. Linq union usage?
  30. LINQ to SQL Where Clause Optional Criteria

Leave a Comment