Adding a value to a line

Olly Fallon

Hi

I am a very novice code and have tried to find solutions online before posting.

in def next(self) I am checking the color of the candle. e.g

 if self.data.open[0] < self.data.close[0]:
            self.candle_color = 'green'

What I cannot work out is how to store this value for accessing in the same way we access other data. e.g

self.candle_color[-1], self.candle_color[-2]

etc

I have tried adding

lines = ('candle_color',)

To the start of the strategy class but this does not appear to make any difference.

If I try and access self.candle_color[-1] it will simply return the "n" of the word "green"

Can anyone point me in the right direction to be able to store this value in the way I need?

Many thanks

EMR

@olly-fallon Not sure if you can set a string as value of a line. Maybe someone who know BT more than me will answer about this.
Why not using an int, or a bool (which basically is a 0/1 value) ?
for example, you can set in the _init of the strategy :

    def __init__(self):
        self.candle_is_green = bt.If(self.data.close > self.data.open, True, False)

and check the result in the next :

    def next(self):
        print(f"self.candle_is_green[0] : {self.candle_is_green[0]}")
        print(f"self.candle_is_green[-1] : {self.candle_is_green[-1]}")
        print(f"self.candle_is_green[-2] : {self.candle_is_green[-2]}")

Note that with this code, if open = close the candle_is_green would be False

Olly Fallon

@emr That's great - I think I can work with it the way you have specified.

Many thanks for taking the time to help out!

EMR

@olly-fallon You are welcome, glad it helped !