Risk management, possible to call account equity?

[PlainStack]

I've been testing different strategies. Core to most of my strategies is to have very tight risk management, i.e. only risk 1% of account on every trade.

For this to work I need to change the size of each trade depending on my distance to the stop loss price. Is it possible to call the account equity in the next() function so I can calculate a variable order size for each trade? Below the variables and the size_long variable I'm trying to solve. I'm not sure if or how to call the account_equity.

    price = self.data.Close[-1]
    sl_short = self.data.Swing_High[-1]
    sl_long = self.data.Swing_Low[-1]
    profit_R = 1.5
    tp_long = price + ((price - sl_long) * profit_R)
    tp_short = price + ((price - sl_short) * profit_R)
    risk = 0.01
    size_long = (risk * account_equity) / (price / sl_long -1)

Feedback is much appreciated!

[PlainStack]

Okay so I tried the below which gives me an outcome that is relatively close, the rounding means it will be slightly more or less that 1% risked. The size _long runs fine but the size_short gives me OverflowError: cannot convert float infinity to integer. So not sure where I'm going wrong or if I'm even on the right track.

    #Risk management/ order sizing
    risk = 0.01
    account_equity = self.equity
    size_long = round(((risk * account_equity) / abs(price / sl_long -1)) / price)
    size_short = round(((risk * account_equity) / abs(price / sl_short -1)) / price)
    print(account_equity, size_short, price, sl_short)

print returns 1000000 144 22883.0 22952.5

Another thing I noticed is that the account equity is the original cash balance I used (1000000) and doesn't change with PnL changes.

[kernc]

OverflowError because you can't round Inf, probably because you're dividing by or something close to 0.

Strategy.equity is a property. In Python, account_equity holds the float value, not the reference.

backtesting.py/backtesting/backtesting.py

Lines 753 to 755 in 65f54f6

	@property
	def equity(self) -> float:
	return self._cash + sum(trade.pl for trade in self.trades)

[PlainStack]

Thanks figured out what was wrong with the error, close == sl. So had to work around it.