Basically what this does is to flag when EMA 55 crosses over EMA 8, 13, 21, and 200. This strategy was described by philakone on this tweet , but I'm not really sure if this is the correct strategy he described.
版本注释
Fixing typo.
版本注释
After reading the comments it looks like EMA 200 shouldn't be taken in count for the crossover so I removed it from the crossover logic.