categorical.isordinal
categorical: TF = isordinal (C)
Test if categorical array is ordinal.
TF = isordinal (C) returns a logical scalar TF,
which is true, if the categorical array C is ordinal, and
false otherwise.
Source Code: categorical
isordinal reports whether the categories carry an order. A plain array is nominal — its categories are just labels with no ranking ...
N = categorical ({'red'; 'green'; 'blue'})
N =
3x1 categorical array
red
green
blue
isordinal (N)
ans = 0
... while one built with 'Ordinal', true is ordered, which is what lets it be compared with < and > and sorted meaningfully.
O = categorical ({'lo'; 'hi'; 'mid'}, {'lo', 'mid', 'hi'}, 'Ordinal', true)
O =
3x1 categorical array
lo
hi
mid
isordinal (O)
ans = 1