I'm sorry you aren't able to read/interpret the file description: "... The arguments are the desired number of selected features (feat_numb), a matrix X, in which each column is a feature vector example...".
what is the meaning "15" in Hy=entropia2([y;zeros(1,C)],15)?
Moreover, the Y dimension is not matched with zeros(1,C). because the Dimension of C is equal with number of features whereas the dimension of y is equal the number of input pairs.
So, there is a mismatch dimension to vertcat!
How we can solve this problem?