This repository contains an optimised version of the Ball Mapper Algorithm To know more about the Ball Mapper Algorithm visit: CRAN package of Ball Mapper Algorithm. The relevant files are also included in this repp in R folder for easy reference.

In this repo, the ball.cpp file contains the optimised code The optimisations are:

• The quadratic procedure of finding and removing duplicate edges has been optimised to $O(nlogn)$. This refers to this block
• The code has been deployed in C++, speeding up the runtime by 100 times

• Run ball.cpp with input file name and epsilon as command line arguments
• The results are stored in files in the root folder
• To use the results in the R file (for visualisations etc) use readBallMapperGraphFromFile with FILENAME (in ball.cpp) as argument

The Boston property dataset (/R/data) was modified to create datasets of different sizes and here are the runtimes of the CRAN implementation and our C++ code:

As can be seen, there is a consistent 100x improvement in runtime.