Qin Jiushao

Qin Jiushao (Chinese: 秦九韶; pinyin: Qín Jiǔsháo; Wade–Giles: Ch'in Chiu-shao, ca.

He is credited for discovering Horner's method as well as inventing Tianchi basins, a type of rain gauge instrument used to gather meteorological data.

In the treatise Qin included a general form of the Chinese remainder theorem that used Da yan shu (大衍术) or algorithms to solve it.

[2][3] Qin recorded the earliest explanation of how Chinese calendar experts calculated astronomical data according to the timing of the winter solstice.

Among his accomplishments are the introduction techniques for solving certain types of algebraic equations using a numerical algorithm (equivalent to the 19th century Horner's method) and for finding sums of arithmetic series.