The reason for broker.get_value() is 'nan'

[Demeen Ma]

version:
Backtrader 1.9.76.123

I think it should redesign the logic of this part of the code:

The logic of calculating value in the program is independent.
After the next(), the code jump to cerebro.py line 1688 self._brokernotify().
And than, jump to line 1355 def _brokernotify(self).
And than, jump to file brokers/bbroker.py & line 1176 def next(self).
And than, jump to line 422 def _get_value(self, datas=None, lever=False)

In this function, the program calculates the cash and value. If broker.get_value() is 'nan', debugging the code here can find the cause of the problem.

Generally speaking, the missing closing price will cause the order price to be 'nan'. Since then, the function get_value() will lose its meaning of existence.