I’m trying to solve Ax = b in matrix.

```
using ToeplitzMatrices
function toeplitz(n)
r = [4; -1; zeros(n-2)]
Toeplitz(r, r)
end
```

and I’m using this function to generate matrix with n [10,100,200,300,400] and try to solve Ax = b (Cholesky factorization)

I found that probably I can use LDL factorization

```
for a in [10, 100,200,300,400]
A = toeplitz(a)
LDLT = ldl(A)
x = LDLT \b
end
```

and gave it `UndefVarError: ldl not defined

Stacktrace:

[1] top-level scope at .\In[34]:3`

I’m not sure what I should change. Or maybe it’s not a good way to resolve this and there is another way ?