Suanpan — Chinese Traditional Calculating Tools

Suanpan is a traditional calculating tool in China, from the Northern Song Dynasty. And suanpan is the intangible cultural heritage too.

Suanpan is different from soroban. And wiki as follows * Suanpan Soroban *.

OpenSCD code : https://github.com/ZhangGaoxing/openscad-models/tree/master/Suanpan

This model's decimal system is in the picture below...