ZǔChōngzhī (AD 429-500) was an outstanding mathematician and scientist in China. He was born in the Southern and Northern Dynasties, Han nationality, and his name is Wen Yuan. Born in the unwritten emperor Yuanjia for six years, he died in the bad emperor Hou Yongyuan for two years. His ancestral home was in Kun County, Fanyang County (now Laishui County, Hebei Province). He moved to Jiangnan. Engage in academic activities. He worked as a historian, a government official, an official of Louxian County (northeast of Kunshan County), a water servant and a captain in South Xuzhou (now Zhenjiang City) all his life. His main contributions are in mathematics, astronomical calendar and machinery. In mathematics, he wrote a book, Composition, which was included in the famous Ten Classics of Computing, but it was later lost. Sui Shu Li Zhi left a short record about pi. The true value of pi calculated by Zu Chongzhi is between 3. 14 15926 (number) and 3. 14 15927 (abundance), which is quite accurate. Become the most advanced achievement in the world at that time. This record was not broken by Arabian mathematician Cassie until15th century. Zu Chongzhi also gave two fractional forms of π: 22/7 (approximate rate) and 355/ 1 13 (secret rate), in which the secret rate is accurate to the seventh decimal place. It was not until the 6th century AD/KLOC-that the Dutch mathematician Otto rediscovered it. Zu Chongzhi, together with his son Zuxuan, successfully solved the problem of calculating the volume of a sphere by using the "Mohe Square Cover" and got the correct formula of the volume of a sphere. Astronomical calendar, Zu Chongzhi created the Daming calendar, and introduced precession into the calendar at the earliest. New leap weeks of 39 1 year and 144 leap months are adopted. For the first time, he accurately measured the data such as the number of months, days (27.2 1223) and the number of days in the return year (365.2428), and also invented a method to determine the time of winter solstice by measuring the length of noon shadow from winter to the days before and after. In mechanics, he designed and manufactured a compass car, a thousand-mile boat and a timer driven by a water hammer mill and copper parts. He also wrote the novel Yi Shu Collection, which is a rare scholar in history. To commemorate this great ancient scientist, people named a crater on the back of the moon "Zu Chongzhi Crater" and an asteroid 1888 "Zu Chongzhi Asteroid". Zu Chongzhi worked hard to calculate the value of pi for the first time in the history of world mathematics. That is, between 3. 14 15926 and 3. 14 15927. He put forward the contract ratio of 22/7 and the secret ratio of 355/ 1 13, which is the earliest in the world, more than a thousand years earlier than Europe, so some people advocate calling it. This book was once regarded as a mathematics textbook by Chinese studies in the Tang Dynasty. His Da Ming Li introduced precession into the calendar for the first time. It is suggested that 144 be set at 39 1 year. The length of a tropical year is 365+0438+0 days, and the error is only about 50 seconds. In addition, he is an outstanding mechanical expert. He recreated many kinds of exquisite machinery, such as the long-lost compass and the thousand-mile ship. Besides, he also studied music. His works, such as Interpretation of the Analects of Confucius, Interpretation of Filial Piety, Yijing, Lao, Zhuang and Yi Shu Ji, have long been lost. [Edit this paragraph] The life of the character. In the history of our country, there was a situation of opposition between the north and the south, which was called the Northern and Southern Dynasties. The Southern Dynasties experienced four dynasties: Song Dynasty, Qi Dynasty, Liang Dynasty and Chen Dynasty, which began when Emperor Wu of the Eastern Jin Dynasty seized the throne in 420 AD. Against the Southern Dynasties was the Northern Dynasties, which experienced the Northern Wei, the Eastern Wei, the Western Wei, the Northern Qi and the Northern Zhou Dynasties. Zu Chongzhi, born in Song Dynasty, died. Agriculture and handicrafts have made remarkable progress, and the rapid development of economy and culture has also promoted scientific progress. So during this period, some very accomplished scientists appeared in the Southern Dynasties, and Zu Chongzhi was one of the most outstanding figures. Zu Chongzhi was born in Kunxian County, Fanyang County (now Laishui County, Hebei Province). At the end of the Western Jin Dynasty, his ancestral home was destroyed by war and moved to the south of the Yangtze River. At the same time, the ancestral home has studied astronomical calendars for generations. So Zu Chongzhi was exposed to technology since he was a child. Zu Chongzhi has a wide range of interests in natural science, literature and philosophy, especially astronomy, mathematics and mechanical manufacturing. He has a strong hobby and in-depth research. As early as his youth, he had a reputation for reading widely and was sent by the government to Hualin University, an academic research institution at that time. Do research work. Later, he served as a local official. 46 1 year, worked in the secretariat of southern Xuzhou (now Zhenjiang, Jiangsu). In 464, the Song government transferred him to Lou County (now the northeast of Kunshan County, Jiangsu Province) as a county magistrate. During this period, Zu Chongzhi continued his academic research and made great achievements, although his life was very unstable. However, he never believed in the ancients. In his own words, never "blindly worship the ancient", but "search the ancient and modern (absorb the essence from a large number of ancient and modern works)". On the one hand, he is interested in the works of ancient scientists Liu Xinwu, Zhang Heng, Liu Hui and Liu Hui. He dared to doubt the conclusions of his predecessors in scientific research, and revised and supplemented them through practical observation and research, thus achieving many valuable scientific achievements. Among astronomical calendars, the Daming Calendar compiled by him was the most accurate one at that time. In mathematics, he calculated pi accurately to six decimal places and achieved the best results in the world at that time.