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Backtest/Live Trading Using too much Capital

So, I have my initial capital set to $100,000.00 (one hundred-thousand) in the backtester and in the live paper trading through Quantopian, and both will allow me to buy unlimited shares, I thought it would throw an error. Is there a way to force it to only use the amount of capital allocated? Thanks!

1 response

Hi Rick,

There's no automatic limit to the amount of money you can spend. The backtester effectively runs as though you're using a margin account. In order to limit the amount of money you spend to your capital base, you will have to manually control the amount that you order. You might want to use context.portfolio.portfolio_value to determine the value of the account and then assign your weights accordingly. You may also need to explicitly manage open orders as explained in Lesson 10 of the Getting Started Tutorial.


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