Eigfact for SymmetricRFP

[mfalt]

I am working on a project where I wanted to do eigenvalue decomposition on Rectangular Full Packed Matrices and found the sspev/dspev functions in LAPACK. Are you still actively working on this package and would you be interested in a PR adding
eig and spev to rectfullpacked.jl and lapack.jl?

[andreasnoack]

Yes, definitely. It's been a long time since I've been looking at the RFP code and it might need some updating. Adding eigen factorizations for the RFP would be great so please prepare a PR.

[mfalt]

It seems to me that a lot of code in this package is broken, with missing imports and similar so I will not spend the time needed to get this up and working. As a reference of some of the things needed to just create a SymmetricRFP, print it and call cholfact (still doesn't seem to produce the right answers) you can look at my branch https://github.com/mfalt/LinearAlgebra.jl but I will settle with only implementing the bare minimum in my own package, you may close this issue if you want. As a reference, I'm running julia 0.5.

[andreasnoack]

I've taken a look at it. Most of the fixes were straight forward. At least when you are used to Julia's linear algebra code but the getindex was little tedious to get right. See JuliaLinearAlgebra/GenericLinearAlgebra.jl#19 where I've also added some tests. Hopefully, the code is now in a state where you can start working on it. Alternative, I'll probably wrap the eigensolvers at some point.