from decimal import Decimal from math import ceil from freqtrade.exceptions import OperationalException one = Decimal(1.0) four = Decimal(4.0) twenty_four = Decimal(24.0) def interest( exchange_name: str, borrowed: Decimal, rate: Decimal, hours: Decimal ) -> Decimal: """ Equation to calculate interest on margin trades :param exchange_name: The exchanged being trading on :param borrowed: The amount of currency being borrowed :param rate: The rate of interest (i.e daily interest rate) :param hours: The time in hours that the currency has been borrowed for Raises: OperationalException: Raised if freqtrade does not support margin trading for this exchange Returns: The amount of interest owed (currency matches borrowed) """ exchange_name = exchange_name.lower() if exchange_name == "binance": return borrowed * rate * ceil(hours)/twenty_four elif exchange_name == "kraken": # Rounded based on https://kraken-fees-calculator.github.io/ return borrowed * rate * (one+ceil(hours/four)) elif exchange_name == "ftx": # As Explained under #Interest rates section in # https://help.ftx.com/hc/en-us/articles/360053007671-Spot-Margin-Trading-Explainer return borrowed * rate * ceil(hours)/twenty_four else: raise OperationalException(f"Leverage not available on {exchange_name} with freqtrade")