[SciPy-Dev] SciPy : GSoC Proposal [Seeking Feedback] on Rotation Formalism in 3 Dimension

[Anubhav Patel]

Hi everyone,
I am want to contribute to SciPy through GSoC 2018. I am currently seeking
feedback on my proposal (
https://docs.google.com/document/d/1ylzugkvVYI7m3IXsWVLD4EkE6zQd8B9YDPKtTno9f74/edit?usp=sharing
). I would appreciate any advice regarding the proposal.

Considering Ralf advice to look for existing implementation, I am currently
looking into few implementation for conversions between rotation
representations, for reuse and inspiration. One of the issues I felt with
almost all of them is that they are designed to work on single rotation at
a time. The API they use sort of suggest towards it. Consider the example
of transforms3d ( http://matthew-brett.github.io/transforms3d/ ), due to
it's API accepting a single rotation at a time, not a array of rotations,
they tend not to utilise numpy vector operations and miss out on the speed
improvement that comes with it.

I decided to reach out to you regarding how useful would the support for
multiple conversions among rotation formalism at once be. It is even worth
considering? How frequent does such a scenario occurs where you have to
convert a sequence of rotation from one formalism to another.

I create a test (code at
https://gist.github.com/anubhavp28/e79645a544c6e7b16b408a172e522134 ) to
see possible improvement with vector operations. I implemented rotation
matrix to quaternion conversion using vector operations and timed it
against what a user would have to do to achieve the same result with
transforms3d. My code took about 0.009185953000269365 while the one with
transform3d took about 0.022295135000604205, for 100 iterations with sample
matrices provided in the code.

I would appreciate any suggestions.

Anubhav Patel
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/scipy-dev/attachments/20180324/76a5c21a/attachment-0001.html>