Iterative insertion of random numbers in matrix

I have a matrix X1.

Now i want to add the sum of two random Numbers

a_x = (-2.5 + (2.5+2.5)*rand(1,1))*1e-9;

l_x = (-2.5 + (2.5+2.5)*rand(1,1))*1e-9;

X1_MC = a_x+l_x

to the value in the first cell of X1.

Then i want to do the same with new random numbers

a_x = (-2.5 + (2.5+2.5)*rand(1,1))*1e-9; % not the same as step1

l_x = (-2.5 + (2.5+2.5)*rand(1,1))*1e-9; % not the same as step1

X1_MC = a_x+l_x

for the secon cell.

I want the process to repeat until the value of each cell in the matrix has been added by two random numbers. The size of X1 is not known

Sorry, I think it is not that compicated but I am new to matlab.

Answer 1

[David Hill]

r1=(5*rand(size(X1))-2.5)*1e-9;
r2=(5*rand(size(X1))-2.5)*1e-9;
Xnew=X1+r1+r2;

[Lucas Kellermann]

But than i would add the same random number to every value in the matrix. Or am I wrong?

I want

r1=(5*rand(size(X1)-2.5)*1e-9;

r2=(5*rand(size(X1)-2.5)*1e-9;

to be recalculated for every cell.

[David Hill]

You are wrong, look at r1 and r2

[Lucas Kellermann]

Oh yes thanks. So simple haha