Here is an interesting fact: Huihui-li is a Chinese translation of a Astronomical handbook with Tables in Farsi from the Islamic world. It was translated at the Islamic Astronomy Bureau in the Chinese Capital. during Kublai Khan’s time. Huihui-li was used in conjunction with the official Chines calendar for more than 300 years. Different versions of Huihui-li are recorded in the Chinese and Korean sources and were even studied by Japanese Astronomers of the time. There is also some evidence that Huihui-li was based on observations made at the Islamic Astronomy Bureau as a result of collaboration between Persian Muslim astronomers and Muslim and non-Muslim Chinese astronomers and thus may not be an exact translation.
Source: Highlights of Astronomy: As Presented at the Xxiiird General Assembly of the IAU, 1997 edited by J. Andersen
Islam in China 
Assalam-o-Alaikum,
Dear Wang,
I need some information not related to this post but a general information. My friend spent sometime in China in Urumqi, Xinjiang. He was telling that there are a lot of Muslims there called Viger. I tried to find more information on Viger but was unsuccessful. Can you please tell me what is Viger and whether it is a right name or not. I will much appreciate if you reply me via Email.
Thank you.
wa’alaikum’as’salam Aamer and welcome to the blog. My apologies for the delayed response. The particular Muslims that your friend is talking about are the Uiygers of Xinjiang
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