KeyError when using multiple dataframes

derdav3

Pretty new to this library.. I'm loading a folder full of quandl csv files like this:

stocks_backtest=[]
for _ in dir_file_list('../stocks/SSE/'):
    stocks_backtest.append(GenericCSV_C(
    dataname=_,
    seperator=',',
    fromdate=datetime.datetime(2016, 01, 05),
    todate=datetime.datetime(2017, 01, 31),

    nullvalue=0.0,
    dtformat=('%Y-%m-%d'),
    datetime=0,
    high=1,
    low=2,
    open=4,
    close=3,
    volume=-1,
    openinterest=-1,
    rsi_6=5,
    rsi_12=6,
    macd=7,
    macds=8,
    adxr=9,
    boll=10,
    boll_ub=11,
    boll_lb=12,
    close_20_sma=13,
    close_50_sma=14,
    close_200_sma=15,
    dma=16))

for idx, stock in enumerate(stocks_backtest):
   stock.plotinfo.plotmaster=stocks_backtest[0]
   cerebro.adddata(stock, name='d'+str(idx))

cerebro.addsizer(TestSizer)
cerebro.broker.setcommission(commission=0.001)

cerebro.run()
cerebro.plot()

However stock.plotinfo.plotmaster leads to a key error:

Traceback (most recent call last):
  File "/home/dav3/Documents/gits/stocks-predictor/backtest/backtest.py", line 64, in <module>
    cerebro.plot()
  File "/home/dav3/.local/lib/python2.7/site-packages/backtrader/cerebro.py", line 927, in plot
    start=start, end=end)
  File "/home/dav3/.local/lib/python2.7/site-packages/backtrader/plot/plot.py", line 220, in plot
    self.plotdata(data, self.dplotsover[data])
  File "/home/dav3/.local/lib/python2.7/site-packages/backtrader/plot/plot.py", line 630, in plotdata
    axdatamaster = self.pinf.daxis[data.plotinfo.plotmaster]
KeyError: <mycsv.GenericCSV_C object at 0x7fe4246c5c50>

when omitting the stock.plotinfo.plotmaster line it compiles, but only seems to consider the first stock. Not sure where to go with this.
thx!

backtrader

One can't be plotmaster of itself. Try:

cerebro.adddata(stocks_backtest[0], name = 'd0')
for idx, stock in enumerate(stocks_backtest[1:], 1):
   stock.plotinfo.plotmaster=stocks_backtest[0]
   cerebro.adddata(stock, name='d'+str(idx))

backtrader

The answer was known because this was already a detected use case and was in the works. You may alternatively try the latest development version which allows plotmaster to reference to the data it belongs to (which allows for a clean loop like the one you were trying)

https://github.com/mementum/backtrader/commit/dd5c0c87b1895a7428b35930cffe8d364d21a271