How do I create a sparse matrix of the following form?

Hello.

Im trying to create a sparse matrix for some vector k, for example [1;2;3], of the following form:

k = [1;2;3];

      1 0 0
      2 1 0
  M = 3 2 1
      0 3 2
      0 0 3

I can not undarstand how to use 'sparse' function to do it. Many thanks for any suggestions!

[SomeUser]

Yeah, I did. I dont understand how to do it without a loop. I've tried s=full(sparse(1:3,1,k,5,3)). Cant add k to 2-nd and 3-rd column.

Answer 1

[Matt J]

 toeplitz(sparse([1,2,3,0,0]) ,sparse([1 0 0]))

[SomeUser]

Thanks alot Matt J. This function is just what I was looking for.

PS: Nice joke btw ;)

[Matt J]

Joke?

[SomeUser]

Yeah, sparse joke. About sparse function.

Weren't you joking? Because there is no need to use it in your code.