What to do with for-while loop?

The question is "Create the matrix based on the probabilities [0.125 0.125 0.125 0.125 0.125 0.125 0.125 0.125] until you get the 1st 8 "

So apparently the question is only asking for the u's and b's so I do not have to compute the list of s. Apparently I need a for-while-loop to fill in values of u and b. How should I do the for-while loop though?

[Torsten]

u = rand()

gives you only one random number.

So over what do you sum in the next line of your code ?

[Sherman Ng]

I think u should be between 0 and 1 and b should be the position of u inside the cdf.

And then I have to do a for-while loop to repeat that step until the answer is equal to 8.

Answer 1

[Torsten]

number_on_dice = 6;
bu = [ ];
while number_on_dice ~= 8
    u = rand();
    number_on_dice = sum(cdf <= u) + 1;
    bu = [bu;[u,number_on_dice]];
end