# Need help creating an matrix that includes probability

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Raul Castillo on 8 Oct 2019
Commented: the cyclist on 8 Oct 2019
So i am asked to make an matrix that is 96x96. this matrix must have a 5% probability of getting a 0 instead of a 1. i know that when creating the matrix i can write
matrix= ones (96,96)
i just dont know how to implement the random generating

the cyclist on 8 Oct 2019
There are many ways to generate pseudorandom numbers in MATLAB. Since this sounds like homework, I'll just point you to this documentation page to get you started.
the cyclist on 8 Oct 2019
You can certainly do the task using randi. But you are correct that your syntax is not the way.
The syntax
randi(100,96,96)
will generate a 96x96 matrix of numbers, where each one is randomly drawn from 1 to 100.
Can you think of a way to then transform that matrix to one with 0's and 1's, where 95% are 1's (on average)?
You could also do a very simliar method using rand instead of randi.

Ajay Kumar on 8 Oct 2019
r = randi([0 1],96,96);
zero_count = round(0.05*numel(r));
count = 0;
for i = 1 : 96
for j = 1: 96
if r(i,j) == 0
count = count+1;
if count > zero_count
r(i,j) = 1;
else
end
end
end
end
the cyclist on 8 Oct 2019
I assume Raul meant that each matrix element has a 5% chance of being zero. This method will not yield that.