Add a benchmark

[FrancoisCarouge]

Is your feature request related to a problem? Please describe.
Benchmarks are critical to demonstrate, compare, test, regress the performance of the library. There is room to add more benchmarks. The library plots its performance. The goal of this story is to add, improve the coverage of the benchmark.

Describe the solution you'd like
One more benchmark source file, plot support in the benchmark directory. Either an absolute benchmark of the library or a comparison against another implementation. The code should be lean, well documented. Give credit and sources where appropriate.