How i can save a random value from a matrix in a variable,exluding values lower than 1?

I have a matrix 100X100 and i want a command to insert in variable pnode a random value of this matrix but,i want the value to be bigger than 1.For example if i have the matrix A=[4 5 2 1; 8 3 1 0] my variable pnode,can take on of the values 4,5,2,8,3 randomly

Answer 1

[Image Analyst]

Try this:

% Generate sample data
A=[4 5 2 1; 8 3 1 0] 
% Get column vector of all the elements where A > 0
A_No_Zeros = A(A > 0)
% Get a random index.
randomIndex = randi(length(A_No_Zeros), 1);
% Assign pnode the random value from A_No_Zeros.
pnode = A(randomIndex)

[Giannakis Stoukas]

It stil gives me pnode=1 and i want to have pnode>1

[Image Analyst]

Sorry - I misread. Just use

A_No_Zeros = A(A > 1)

instead.

[Giannakis Stoukas]

Well i followed the commands you wrote,but after a number of repeats my value takes the number one.Although at the results it writes that the minimum value of A_No_Zeros is value 2.I really dont get why this happens.

[Image Analyst]

Because once you ignore 0's and 1's in [4 5 2 1; 8 3 1 0] you are left with [4 5 2 8 3] and the minimum of that is 2. Not sure why you're surprised. However my code did not compute the minimum so that must be code you added.