Previous instalments

General Data Structures

• HashList

Trees

• GeneralTree and the Visitor Pattern
• Binary Trees and Binary Search Trees

Looking at tree structures will make your eyes bleed, so we’ll take a break to discuss one of the simpler data structures NGenerics offers - the ObjectMatrix. The ObjectMatrix is a representation of a 2-dimensional array of objects, like, for example, a game board :

Why not use a two-dimensional array in the first place?  The ObjectMatrix offers the following useful operations at the time of writing:

• Rows and Columns - formal definition of rows and columns - much better than having .Length scattered all over your code.
• GetSubMatrix -  enables the retrieval of a subset of the matrix.
• InterchangeRows and InterchangeColumns - swap individual rows and columns.
• GetRow and GetColumn - provides an easy way of retrieving individual rows and columns.
• AddRow and AddColumn - add new rows and columns when you need more space.
• DeleteRow and DeleteColumn - delete individual rows and columns.
• Resize - resize the matrix to have any arbitrary column/row count.

Use it like you would use any two dimensional array :

var matrix = new ObjectMatrix(3, 3);
matrix[0, 0] = new Cross();
matrix[0, 1] = new Nought();
matrix[0, 2] = new Nought();
matrix[1, 0] = new Nought();
matrix[1, 1] = new Cross();
matrix[2, 2] = new Cross();

var enumerator = matrix.GetEnumerator();

while (enumerator.MoveNext())
{
    Console.WriteLine(enumerator.Current);
}

The ObjectMatrix is also the base class for one of the biggest classes in NGenerics - the mathematical Matrix, which we’ll get to in a later post.

Photo by Markus Spiske on Unsplash

See also

• NGenerics - new team member
• NGenerics 1.4.1 Beta released
• NGenerics has moved
• NGenerics project move update
• NGenerics overview - the Priority Queue