Below you find some common problems in Julia that we have noticed that people run into during handin 2:



Problem: You get the error: "Error: warn not defined...." when using ProximalOperators

Solution: Input copy(X') instead of X' to the function, or update ProximalOperators using:
using Pkg; Pkg.update();

Explanation: Transposing a Matrix X in Julia results in a special Adjoint{Matrix} X'.
Not all functions are made to handle this. This was updated in ProximalOperators on 2019-09-25.




Problem: You get the error "ERROR: UndefVarError: R not defined"

Solution: The lambda argument should be a Float (1.0) instead of Int (1)

Explanation: The function expects lambda to be of the same type as the elements in the matrix and vector.