Check out the order_target_value method, you can do something like:
to order $1,000 worth of context.stock
Alternatively you could use the order_target_percent method to allocate a fixed percent of your total portfolio value, for example:
Will place an order of context.stock equal to 10% of your total portfolio value.
One gotcha with these convenience methods is that they do not check for open orders, so if you are simulating with illiquid stocks using a conservative slippage model you may still hit an over-ordering scenario. We're working on ways to make that easier, but careful backtesting and defensive coding are good best practice for now.
Best wishes, Jess
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