Theon of Alexandria

Theon of Alexandria (c. 335-c. 405 CE) was a Greek mathematician and astronomer who worked at Alexandria and is known for his editions of and commentaries on earlier mathematical works, including an influential edition of Euclid's Elements and commentaries on Ptolemy's astronomical writings. He was the father of the mathematician and philosopher Hypatia. He is distinct from the earlier Theon of Smyrna.