getMaxIndexOfRows: Find row- or columnwise the index of the maximal / minimal element in a matrix.
Description
getMaxIndexOfRows returns the index of the maximal element of each row.
getMinIndexOfRows returns the index of the minimal element of each row.
getMaxIndexOfCols returns the index of the maximal element of each col.
getMinIndexOfCols returns the index of the minimal element of each col.
If a corresponding vector (row or col) is empty, possibly after NA removal, -1 is returned
as index.