Sorting direction must be ''descend'' or ''ascend'' Sorting direction must specify one direction or a direction for each sorting variable. The input table does not contain row names, returning the requested number of rows unsorted. Numeric variable indices must be positive integers. Sorting variable ''{0}'' has more than 2 dimensions. Unable to sort variable ''{0}'' of type ''{1}''. Cell array sorting variables must contain character vectors. Number of rows to return must be a nonnegative integer.