Global Currency Value Strategy Using OECD PPP Adjusted by CPI and Exchange Rates

# Import the algorithm base and dictionary collection from external libraries.
from AlgoLib import algorithm
from System.Collections.Generic import Dictionary

# Define the class PPPBasedCurrencyStrategy which inherits from an unspecified class XXX.
class PPPBasedCurrencyStrategy(XXX):
def Initialize(self):
"""Initializes the trading algorithm with starting conditions and data subscriptions."""

# Set the start date of the algorithm to January 1st, 2000.
self.SetStartDate(2000, 1, 1)

# Set the initial cash to $100,000.
self.SetCash(100000)

# Define leverage and the number of symbols to trade.
self.leverage = 3
self.symbols_to_trade = 3

# Initialize an empty dictionary to store purchasing power parity data.
self.purchasing_power_parity = {}

# Define a mapping between future symbols and their corresponding PPP symbols.
self.future_to_ppp_mapping = {
    "CME_AD1": "AUS_PPP",
    "CME_BP1": "GBR_PPP",
    "CME_CD1": "CAD_PPP",
    "CME_EC1": "DEU_PPP",
    "CME_JY1": "JPN_PPP",
    "CME_NE1": "NZL_PPP",
    "CME_SF1": "CHE_PPP"
}

# Subscribe to futures data and purchasing power parity data for each mapped symbol.
for future_symbol, ppp_symbol in self.future_to_ppp_mapping.items():
    self.AddFuture(future_symbol, Resolution.Daily, self.leverage)
    self.AddData(custom.PurchasingPowerParity, ppp_symbol, Resolution.Daily)

# Set the minimum order margin as a percentage of the portfolio to 0.0, allowing for higher leverage.
self.Settings.MinimumOrderMarginPortfolioPercentage = 0.0

# Initialize a variable to keep track of the last month processed.
self.last_month_processed = None

def OnData(self, data):
"""Handles new data events and decides when to rebalance the portfolio."""

# If the current month is the same as the last processed month, do nothing.
if self.Time.month == self.last_month_processed:
    return

# Update the PPP data with the latest values.
self.UpdatePPPData(data)

# Update the last processed month to the current month.
self.last_month_processed = self.Time.month

# If it's January, rebalance the portfolio.
if self.Time.month == 1:
    self.RebalancePortfolio(data)

def AddFuture(self, symbol, resolution, leverage):
"""Adds a future to the data subscription with specified leverage."""
   
# Add the future data to the algorithm with specified resolution.
future = self.AddData(custom.QuantpediaFutures, symbol, resolution)

# Set the leverage for the future.
future.SetLeverage(leverage)

# Return the future object for further use (if needed).
return future

def UpdatePPPData(self, data):
"""Updates the purchasing power parity data for each symbol in the mapping."""

# Iterate through each symbol and its corresponding PPP symbol.
for symbol, ppp_symbol in self.future_to_ppp_mapping.items():
    
    # If the PPP symbol data is available in the new data, update the PPP data dictionary.
    if ppp_symbol in data:
        self.purchasing_power_parity[symbol] = data[ppp_symbol].Value

def RebalancePortfolio(self, data):
"""Rebalances the portfolio based on the purchasing power parity data."""

# Check if there's enough PPP data to rebalance the portfolio.
if len(self.purchasing_power_parity) >= self.symbols_to_trade * 2:
    
    # Sort the symbols by their PPP value.
    sorted_symbols = sorted(self.purchasing_power_parity.items(), key=lambda x: x[1])
    
    # Select symbols for long positions (the ones with highest PPP).
    long_symbols = [symbol for symbol, _ in sorted_symbols[-self.symbols_to_trade:]]
    
    # Select symbols for short positions (the ones with lowest PPP).
    short_symbols = [symbol for symbol, _ in sorted_symbols[:self.symbols_to_trade]]

    # Clear the PPP data for the next rebalance.
    self.purchasing_power_parity.clear()
    
    # Execute the trades based on the selected long and short positions.
    self.ExecuteTrades(long_symbols, short_symbols, data)

def ExecuteTrades(self, long_symbols, short_symbols, data):
"""Executes the trading strategy by setting holdings based on desired long and short positions."""

# Liquidate positions that are no longer in the selected long or short symbols.
for symbol in self.Portfolio.keys():
    if symbol not in long_symbols + short_symbols and self.Portfolio[symbol].Invested:
        self.Liquidate(symbol)

# Set holdings for long positions, equally distributing the investment.
for symbol in long_symbols:
    if symbol in data:
        self.SetHoldings(symbol, 1 / len(long_symbols))

# Set holdings for short positions, equally distributing the investment.
for symbol in short_symbols:
    if symbol in data:
        self.SetHoldings(symbol, -1 / len(short_symbols))