How to build a ''growing" matrix

In my example I have:

variable "i" (size 1x1) and R (size 3x3)

R = 1     0      0
    0   cos(i) sin(i)
    0  -cos(i) cos(i)

Now, how should I build "R" if my variable "i" has size 1 x n?

[Azzi Abdelmalek]

What is the size of R?

[Sebastian Ciuban]

Well in the simple case lets say:

i=1
R=1     0      0
  0   cos(i) sin(i)
  0  -cos(i) cos(i)

But what if i=[1 3 5 5]. How I can make R to be computed for all the values of i?

Answer 1

[Image Analyst]

cos(i) will be an array if i is an array. So that means that the elements of R must be cells since all elements of R are not the same size. The firs row and column of R are 1x1 while the lower right elements are 1 x 4. I really think you should avoid this route, but if you insist, start your study of cells here in the FAQ: http://matlab.wikia.com/wiki/FAQ#What_is_a_cell_array.3F. You'd probably be better off making R a 3D array though, with each plane of R being computed for a different value of i. Let us know which approach you want to take. If you don't know , then let us know what you plan on doing with R once you have it.

[Sebastian Ciuban]

Shall I write my code and explain what is my final purpose?

[Image Analyst]

Yes, why wouldn't you?