# Code

# Sagemath

Sagemath (http://sagemath.org) is a free open-source mathematics software system started by my thesis advisor William Stein. The Sagemath library is primarily written in Python and Cython. Most of my contributions are written in Python.

#### Bigger Sagemath Projects

##### GSoC

In 2016, I was able to spend the summer working on Sagemath. I collaborated with William Stein (https://github.com/williamstein/sage_modabvar) to improve the modular abelian variety functionality of Sagemath. Eventually this project morphed into my thesis project. This code has since been merge back into Sagemath.

##### Isomorphic Testing

As part of my thesis, I enumerated the isogeny class of simple modular abelian varieties, up to isomorphism. Informally, two objects in mathematics are isomorphic if they’re effectively the same. A necessary step in my enumeration is then to be able to determine when two simple modular abelian varieties are isomorphic. The key idea is use the fact that endomorphism rings of simple modular abelian varieties are isomorphic to orders of number field to reduce isomorphic testing to solving norm equations. I’ve implemented this functionality and have submitted a ticket.

# Caleb

`caleb`

(https://github.com/kevinywlui/caleb) is a Python package that helps
fill in bibtex entries using http://crossref.org. My usual workflow in Latex
is to write `\cite{mazur:eisenstein}`

and then look up a bibtex entry with
author field containing mazur and title field containing eisenstein, and then
append it to my `biblio.bib`

file. The purpose of `caleb`

is to do this
automatically with the http://crossref.org API.

At it’s core, `caleb`

is a pretty simple program. My primary motivation for
writing `caleb`

was to learn making a `pip`

installable package, using
`pytest`

, setting up `travis`

, and using `poetry`

.

# oeiswall

`oeiswall`

(https://github.com/kevinywlui/oeiswall) is a quick little Python
script to make a nerdy wallpaper with data coming from OEIS.