Obake (お化け) [...] are a class of yōkai, preternatural creatures in Japanese folklore. Literally, the terms mean a thing that changes, referring to a state of transformation or shapeshifting.

obake is a C++20 library for the symbolic manipulation of sparse polynomials and other closely-related mathematical objects (e.g., truncated power series, Poisson series, etc.). obake is the successor of the piranha project.

If you are using obake as part of your research, teaching, or other activities, we would be grateful if you could star the repository and/or cite our work. The DOI of the latest version and other citation resources are available at this link.

obake is under active development. Preliminary documentation (including installation instructions) is available here.