double[,], int[], bool[] … matrix,vector manipulation extensions in C#

Question

I need(for rapid prototyping and libraries integration) something like this(extensions for usual arrays)

double[] d;
d.SetRow(1,{ 1.1 , 2.0 ,3.3});
var r = d.GetRow(1);
d = d.AppendRight(new int[]{1,2,3});
...

Does exist such thing anywhere? On may be anybody implemented it so I do not need do i for me myself?

Answer 1

This shouldn't be too difficult to write yourself.

The thing to be very careful of is how arrays can be edited as properties.

Something like (very rough untested code, but should give you an idea):

public class ArrayRow<T> {
    //add your own ..ctor etc

    T[,] matrix; //don't make this public see http://msdn.microsoft.com/en-us/library/k2604h5s.aspx
    public int Index { get; private set; }

    //note that this will be a copy
    public T[] GetValues() {
        T[] retval = new T[matrix.GetLength(1)];
        for ( int i = 0; i < retval.Length; i++ )
           retval[i] = matrix[Index, i];

        return retval;
    }

    public void SetValues(T[] values)
    //..and so on, you get the idea
}

Then you extend the array:

public static ArrayExtensions {

    public void SetRow<T> ( this T[,] matrix, int rowIndex, T[] values ) {
        //check rowIndex in range and array lengths match
    }

    public ArrayRow<T> GetRow<T> ( this T[,] matrix, int rowIndex ) {
        //check rowIndex in range
        return new ArrayRow<T> ( matrix, rowIndex );
    }
}

Then you can rely on the type parameter being inferred.

Answer 2

Have a look at Math.NET. It is an open-source math library. You will probably find what you need.

They have an example using a matrix at the end of this page.

Answer 3

Languages like Python support lists with mixed types. You can create an IronPython script and then call it from your C# application. Follow this link to see how you can call IronPython script from your app.

Answer 4

I wrote Matrix Extensions C# library to test extensions based code generation design.