GSoC Week 2
After the Kalevi’s comment
The paramrde branch is getting inconveniently big for hunting down and reviewing small changes. I think we should create another branch that would contain my original PR plus the added limited_integrate code (and optionally something else). Then that should be merged. Thereafter it would be easier to review new additions.
I decided to remove a few commits from top of paramrde
branch and made the branch paramrde
mergeable.
Yesterday Kalevi merged the pull request #11761, Parametric Risch differentia equation, there were quite a few problems(unrelated to my work) with travis but finally it passes the tests.
So till now these are pull requests that have been completed/started for my project:

Merged:
paramrde #11761: This is the pull request that Kalevi made back in september 2016. I further made commits for
limited_integration
function, implementation of parametric risch differential equation, though not many tests were added in this, which should definitely be done. I haven’t been able to find tests that lead to noncancellation cases (Kalevi mentions that we should be able to find them), so for the time being we decided to start the implementation of cancellation routines, particularly liouvillian cases (others being nonlinear and hypertangent cases), there isn’t a good reason to implement the hypertangent cases right now. 
Unmerged:
paramrde_polymatrix this pull request is intended to use
PolyMatrix
instead ofMatrix
(it isMutableDenseMatrix
), here is Kalevi’s comment regarding it: “It would also be possible to use from … import PolyMatrix as Matrix. That would hint that there might be a single matrix in the future.”. The reason for making isMatrix
doesn’t play well withPoly
(or related) elements. 
Merged:
Change printing of DifferentialExtension object, it wasn’t necessary to make this pull request, but it does help me in debugging the problems a little easier.
I was hoping that I would write a bit of mathematics in my blog posts, but unfortunately things I have dealt with till now required me to focus on programming API, introducing PolyMatrix
so it deals well with the elements of Poly
’s, but I am thinking this week I am going to deal with more of mathematics.
TODO for this week
 Complete the cancellation liouvillian cases. I just sent the pull request for it Liouvillian cases for Parametric Risch differential equation #12743. I really need to catch with the core of things, do it a little quick.
I hope the next blog post is going to be a good mathematical one :)