Hello, I’m actually new to Julia and trying many different tutorials along with the documentation in order to get a better understanding of the language until I start using it in a more fluent way. I’ve seen in one of the tutorials of the Julia academy two methods for matrix factorization qrfact and lufact both of which I cannot find in the LinearAlgebra package. I’m using Julia 1.5.2 and started to wonder if these functions have been removed in an update because I had the same issue when trying to take a broadcast transpose of a matrix A.’ . Is that the case, or am I missing something?
Hi! Looks like they have been renamed to qr
and lu
.
Oh cool ok. I’ve seen these two but thought they are somewhat different due to multiple dispatch. Good to know. Thanks
You should look at lu! and qr!. The ones with a ! overwrite the matrix, just like dgefa from LINPACK. Try this and get a few screenfuls of useful stuff.
julia> ?
help?> lu!
Yeah, now that I’ve checked those two I can see that they follow the ! convention, and you can extract Q, R, L, U, P from both mutating and non-mutating versions with a dot operator. Thanks