The provided strategy is a basic implementation of a trading strategy that uses the Moving Average Convergence Divergence (MACD) indicator. Here's a simplified description of what the strategy does:
The strategy defines a class called Strat that inherits from IStrategy, indicating it's a trading strategy implementation. The populate_indicators method takes a DataFrame of historical market data and a metadata dictionary as inputs.
It initializes a list called should_buy with False values, representing whether to buy at each data point.
The method then iterates over each data point in the DataFrame and calculates a subset of the DataFrame called dataframe_slice up to the current data point.
Within each iteration, it checks if the MACD value at the current data point is less than the MACD signal value at the current data point in dataframe_slice. If it is, it sets the corresponding should_buy value to True. Finally, the should_buy list is added as a new column called "should_buy" in the original DataFrame, and the modified DataFrame is returned. The populate_buy_trend method takes the modified DataFrame and metadata as inputs. It sets the "buy" column to 1 for rows where the "should_buy" column is True. The modified DataFrame with the "buy" column updated is returned. This strategy essentially generates a signal to buy (setting the "buy" column to 1) when the MACD is below the MACD signal. The backtesting website can use this strategy to simulate trading decisions based on historical data and evaluate its performance.