Candlestick barup plotting color not working correctly?
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Hi everyone,
I'm doing the most basic examples from the README page and simple tutorials online, and I'm plotting my graph the following way:
cerebro.plot(style='candlestick')
or
cerebro.plot(style='candlestick', barup='green', bardown='red')
However, my graph looks almost entirely red when plotted:
Verbatim copy/paste examples are showing the above type of output, but blog posts show red/green gray/green mixtures (as it should). Any thoughts on what is going wrong?
I appreciate the help, thanks!
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Let's assume that you have recently downloaded that data from Yahoo ... and given that the data is now not really usable and what's adjusted close and real close is just a matter of in which direction the wind blows ... it could be a reason for the candles looking downwards in most cases.
See a recent thread for example: https://community.backtrader.com/topic/552/incorrect-corrupted-data-retrieved-when-using-yahoofinancedata-api/
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@nomnom, I agree with what @backtrader says. If you retrieved the data from Yahoo like I did (in my case using
YahooFinanceData), you will observe random inconsistencies (sometimes, everything is fine, sometimes, everything is bad up to a point and then gets better**, sometimes the whole dataset is bad). If you read the post which @backtrader referenced, you will see that I had exactly the same issues when I tried to plot the data using candlesticks.Try seeing if you get the same problem with a different data source (e.g. Quandl).
** Try extending the timeframe for your example (make it go all the way up to yesterday). I'm willing to bet that you'll see that it "improves" after a certain date.
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Oh wow, thanks for the feedback. That post certainly has a lot of information. I'm a bit confused though, getting this data is an absolute critical part to be able to perform meaningful backtesting. How is everyone getting their data? Surely everyone isn't making one-off modifications, are they? I have to assume I'm being dumb here and there is a common source/service/method that everyone uses to get reliable, meaningful data.
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I don't know how accurate this is, but this ended up working:
import backtrader as bt
import pandas_datareader as web
...
feed = web.DataReader("AAPL", "google", datetime(2016, 1, 1), datetime(2017, 1, 1))
data = bt.feeds.PandasData(dataname=feed, name="AAPL")
cerebro.adddata(data)
cerebro.run()
cerebro.plot(style='candlestick', barup='green', bardown='red')The graph looks as expected. Not sure if the data is exactly correct though.