[blackcat] L0 Understand request.security_lower_tf() function

Level 0

Background

I am learning to use new function request.security_lower_tf() to realize some new features.

Function
Requests data from a lower timeframe than the chart's. The key difference is that the return is no longer series type but array. If you want to combine lower tf with higher tf to form a mtf, you may need to be good at array operations.

This is a very simple demonstration for request.security_lower_tf(), you will see how array grows under 15min tf with 1min intrabar data changes. It may help you understand how request.security_lower_tf() easier.

Remarks

Feedbacks are appreciated.

版本注释:

Add intrabar status indicator: 0~1 line and bgcolor change from green to red