ranknum

compute the rank number (rankings) of elements

R = ranknum(V) returns the rank numbers of the elements of the (numerical) vector V, using the dense ranking procedure for ties (see below).
NaNs are ignored (rank NaN). R has the same size as V.

R = ranknum(V, P) ranks V according to the ranking procedure P, which specifies how to deal with values that tie for the same ranking position. P is a number from 1 to 5.
1 - Dense "1223"
2 - Ordinal "1234"
3 - Competition "1224"
4 - Modified Competition "1334"
5 - Fractional "1 2.5 2.5 4"

V can be a cell array of strings, for which alphabetical ordering is used.

For more info on ranking, see https://en.wikipedia.org/wiki/Ranking