Which line in the data is SimpleMovingAverage based on?

[kaluzagonzo]

In https://www.backtrader.com/docu/concepts.html , a moving average is constructed like this:

sma = btind.SimpleMovingAverage(self.datas[0], period=self.params.period)

Wouldn't self.datas[0] contain several lines, i.e. self.datas[0].lines.close, self.datas[0].lines.open, self.datas[0].lines.min, etc. according to whatever columns are in our data table?

Which of these lines is the SMA based on? Follow up: does it ASSUME that we want compute SMA on "close" and are therefore required to include a "close" line in every data feed that is sent to the SMA function?

[backtrader]

No. If no specific line is passed, the 1st defined line is used. In the case of regular data feeds, close is defined as the 1st line to match the de-facto standard which is to do things directly on the close price.