/// <summary>Enumerates indices in this collection.</summary>
/// <param name="source">Source for the.</param>
/// <param name="f">The Func<Vector,bool> to process.</param>
/// <returns>
/// An enumerator that allows foreach to be used to process indices in this collection.
/// </returns>
public static IEnumerable <int> Indices(Matrix source, Func <Vector, bool> f)
{
return(Matrix.Indices(source, f, VectorType.Row));
}