How do I create a lower triangle matrix from a single column matrix.

If I have a script that returns its answers in this format:

A=[1;2;3;4]

How do I create a matrix that looks like this:

B=[1 0 0 0;2 1 0 0;3 2 1 0;4 3 2 1]

Answer 1

[Guillaume]

tril(toeplitz(A))

is an option

[Jessca Sudderth]

THANK YOU!!