Programmatically Creating a Nested Array

Hi MathCad Experts,

Step 1 I have a 3x3 matrix t[1] with 1's and 0's . I want to insert another 3x3 matrix "One" into U if the element of t[1] is 1 other insert 3x3 matrix zero as a Nested Array.

Step 2 Convert to a Matrix.

I have not done this previously so I would like your suggests/help.

Thanks.