/// <summary>
/// Gets the lower triangular part of a matrix.
/// </summary>
///
public static T[][] GetLowerTriangle <T>(this T[][] matrix, bool includeDiagonal = true)
{
int s = includeDiagonal ? 1 : 0;
var r = Jagged.CreateAs(matrix);
for (int i = 0; i < matrix.Rows(); i++)
{
for (int j = 0; j < i + s; j++)
{
r[i][j] = matrix[i][j];
}
}
;
return(r);
}
public static T[][] KHot <T>(bool[][] mask)
{
return(KHot <T>(mask, Jagged.CreateAs <bool, T>(mask)));
}
///// <summary>
///// Determines whether a jagged array is a rectangular
///// matrix (containing all inner arrays of same size).
///// </summary>
/////
//public static bool IsRectangular<T>(this T[][] array)
//{
// if (array.Length == 0)
// return true;
// int cols = array[0].Length;
// for (int i = 0; i < array.Length; i++)
// {
// if (array[0].Length != cols)
// return false;
// }
// return true;
//}
#endregion
#region Operation Mapping (Apply)
/// <summary>
/// Applies a function to every element of the array.
/// </summary>
///
public static TResult[][] Apply <TInput, TResult>(this TInput[][] matrix, Func <TInput, int, int, TResult> func)
{
return(Apply(matrix, func, Jagged.CreateAs <TInput, TResult>(matrix)));
}
