How to structure an algo into two files?

Based on the information provided, it seems like you're trying to access the Log method of the QCAlgorithm class from another class. The Log method is an instance method of the QCAlgorithm class, so it needs to be called on an instance of the class.

In your B class, you're trying to call UglyBluePig.Log("This is a test"), but UglyBluePig is a class, not an instance of the class. You need to have an instance of the UglyBluePig class (which is a subclass of QCAlgorithm) to call the Log method.

One way to do this is to pass an instance of the UglyBluePig class to the B class when you create an instance of B. Here's an example of how you might do this:

class UglyBluePig(QCAlgorithm):
    def Initialize(self):
        self.SetStartDate(2024, 2, 1)
        self.SetCash(100000)
        self.AddEquity("SPY", Resolution.Hour)
    def OnData(self, data: Slice):
        if not self.Portfolio.Invested:
            self.SetHoldings("SPY", 0.33)

class B:
    def __init__(self, algo):
        self.algo = algo
    def call_a(self):
        self.algo.Log("This is a test")

Then, when you create an instance of B, you would pass in an instance of UglyBluePig:

ugly_blue_pig = UglyBluePig()
b = B(ugly_blue_pig)
b.call_a()  # This will call the Log method on the UglyBluePig instance

This way, the B class has a reference to an instance of the UglyBluePig class, and it can call the Log method on that instance.

Please note that this is a simplified example and might not work directly in your algorithm depending on your setup. You might need to adjust it to fit your specific needs.

Hello Mia,

Thank you very much for your quick answer with such a detailed explanation about classes and instances. Your help is greatly appreciated and I will definitely study more on both.

I followed your indications and the error disappeared. However neither self.algo.Log nor self.algo.Debug functions generate any text when called from OnData which makes me believe it is not possible to use another instance of the UglyBluePig class (which is a subclass of QCAlgorithm). I am in the attached backtest that b.call_a method is being executed because of the “2” being returned (see attached backtest).

What I'm ultimately trying to do is combine two algos with quite lengthy OnData methods into one single algorithm in the most structured and object oriented way. Maybe you can suggest the best way to do this since they both need access to al the QCAlgorithm class, OnData method and the same Portfolio object.

Hi Andres Arizpe 
You need to make a small change to get the functionality you are looking for.
Instead of creating a new object for the “UglyBluePig” class, you can pass “self” as an attribute to the object of class “B” to get access to Log and Debug functionalities.
Changed code:

b = B(self)

Output:

Backtest Attached.
Let me know if this is helpful!
Best,
Ashutosh

Hi Ashutosh,

Your answer was spot on. I am now able to access not only QCAlgorithm methods from another file but all objects by just placing “self.algo” instead of “self”.

Even though this might not be the best object oriented programming, I believe this is a very useful template for combining two or more algos in order to increase profits or reduce risk and hopefully someone else wll benefit.

I've attached a simple example using the Supertrend (STR) indicator which has a decent predictive power but when combining multiple low correlation assets may create consistent positive alpha.

Cheers,

Andres