Abu'l-Hasan ibn Ali al-Qalasadi

Abū'l-Ḥasan ʿAlī ibn Muḥammad ibn ʿAlī al-Qurashī al-Qalaṣādī (Arabic: أبو الحسن علي بن محمد بن علي القرشي البسطي; 1412–1486[1]) was a Muslim Arab[2] mathematician from Al-Andalus specializing in Islamic inheritance jurisprudence.

His works dealt with Algebra and contained the precise mathematical answers to problems in everyday life, such as the composition of medicaments, the calculation of the drop of irrigation canals and the explanation of frauds linked to instruments of measurement.

The second part belongs to the already ancient tradition of judicial and cultural mathematics and joins a collection of arithmetical problems presented in the form of poetical riddles.

In 1480 the Christian forces of Ferdinand and Isabella, "The Catholic Monarchs", raided and often pillaged the city.

Al-Qalasādī eventually left his homeland and took refuge with his family in Béja, Tunisia, where he died in 1486.