2. Zu Chongzhi (AD 429- AD 500) was an outstanding mathematician, astronomer, writer, geologist, geographer and scientist in China.
Zu Chongzhi calculated the value of pi to seven decimal places for the first time in the history of mathematics in the world, that is, between 3. 14 15926 and 3. 14 15927. He proposed an approximate ratio of 22/7 and a density ratio of 355/ 1 165438. So some people advocate calling it "ancestral rate", that is, the ancestor of π. He compiled his mathematics research results into a book called Composition, which was once designated as a mathematics textbook by the Chinese studies in the Tang Dynasty. "Precession" was first introduced into the calendar. It is suggested that 144 leap month be set at 39 1 year. The length of a tropical year is 365.4438+045438+0 days, and the error is only about 50 seconds. He is not only an outstanding mathematician and astronomer, but also an outstanding mechanic expert. He also studies music. His works include The Analects of Confucius, Xiao Jing, Yijing, Lao, Zhuang and Yi Shu Ji, but they have long been lost.
3. Li Daoyuan (about 470-527) is a good writer. Han nationality, Fanyang Zhuolu (now Zhuolu County, Hebei Province). He was a geographer and essayist in the Northern Dynasties and the Northern Wei Dynasty. His career was bumpy, but he didn't do his best. He has read many wonderful books. When I was a child, I traveled with my father in Shandong to seek waterways. Later, I traveled to Qinling Mountains, north of Huaihe River and south of the Great Wall, inspected river ditches and collected relevant customs. It is not only a colorful geographical work, but also a collection of beautiful landscape essays. It can be regarded as the pioneering work of China's tourism literature, which has a great influence on the development of later tourism prose. Thirteen articles, such as local chronicles and Seven Covenants, have been lost.
4. Jia Sixie (Ji γ s γ xié) was born in the Northern Wei Dynasty (AD 386 ~ 543), a native of Yidu (now southwest of Shouguang City, Shandong Province), lived in the late Northern Wei Dynasty and the Eastern Wei Dynasty (6th century AD) in China, and served as the prefect of Lai County (now Linzi, Shandong Province). He was an outstanding agronomist in ancient China. In addition, there is a preface and a miscellaneous talk in front of the book. There are more than 50 kinds of previous works/kloc-0, and more than 30 agricultural proverbs are recorded. The book introduces the cultivation methods of crops, vegetables and fruit trees, the production of various economic trees, the utilization of wild plants, the feeding of livestock, poultry, fish and silkworms and the prevention and treatment of diseases, as well as the processing, brewing and food processing of agricultural and sideline products and livestock products.