Determining probability mass function of random variable

Question

If we have a discrete random variable x and the data pertaining to it in X(n), how in matlab can we determine the probability mass function pmf(X)?

Answer 1

How about this function?

function Y = pmf(X)
A=tabulate(X)
A(:,3)=A(:,3)/100
Y=A(:,3)'

Is this correct in your opinion?