How do I generate a uniform random number from a 2d matrix to form a 3d matrix

I have a vector A, such that A is 48X1, I need to create another matrix B from A, such that B is 48X1X5000 (i.e. a 3D matrix). Now I want all element in the first row of matrix B to be a random number that is within 0.8 times and 1.2 times the element in the first row of matrix A. All element in the second row of matrix B to be a random number that is within 0.8 times and 1.2 times the element in the 2nd row of matrix A. All element in the third row of matrix B to be a random number that is within 0.8 times and 1.2 times the element in the third row of matrix A, and so on till the 48th row. Remember B is a 3D matrix of 48 by 1 by 5000. Thank you. Looking forward to your support.

Answer 1

[James Tursa]

E.g., later versions of MATLAB:

A = whatever;
f1 = 0.8;
f2 = 1.2;
n = 5000;
B = A .* (f1 + rand([size(A) n])*(f2-f1)));

Or earlier versions of MATLAB:

B = bsxfun(@times,A,f1 + rand([size(A) n])*(f2-f1));

[Onovo]

Thank you, will give it a try.