Frequently asked questions, Computational Algebra

Q: What is meant by growth factor in Assignment 1.2?

A: The quotient between the largest element in factors L and U and the largest element in the original matrix A. A large growth factor means that you get a large rounding error.

Q: What is meant by error in the solution in Ass 1.2?

A: If you know the exact solution  it is
Otherwize you use the residual
Try with an arbitrary vector b! Often the error is growing faster than the residual, when the matrix gets ill conditioned.

Q: How do I make my files availble to my collaborator?

A: Try the fs command! I think you should write
>fs setacl catalogue-name other-user rlidw
Replace italic text by the appropriate. The last is a set of options
r read
l list
i insert
d delete
w write