Problem--when I try the guide code

[xue]

else:
# in market we might sell
if len(self) >= (self.bar_executed + 5):
self.log('Sell create, %.2f' % self.dataclose[0])

            self.order = self.sell()

File "e:\trading\backtrader_ex\backtrader\cerebro.py", line 1695, in _runonce
strat._oncepost(dt0)
File "e:\trading\backtrader_ex\backtrader\strategy.py", line 309, in _oncepost
self.next()
File "e:/trading/backtrader_ex/test.py", line 46, in next
if len(self) >= (self.bar_executed + 5):
File "e:\trading\backtrader_ex\backtrader\lineseries.py", line 461, in getattr
return getattr(self.lines, name)
AttributeError: 'Lines_LineSeries_LineIterator_DataAccessor_Strateg' object has no attribute 'bar_executed'

[run-out]

@xue said in Problem--when I try the guide code:

f len(self) >= (self.bar_executed + 5):

Look like self.bar_executed doesn't exist. Other than that, given the limited information you have provided, cannot really provide you with assitance. If you wish, you could copy all of your code here between triple backslashes (see instructions at the top of this page) and then maybe we can help you.

[xue]

@run-out from future import (absolute_import, division,
print_function, unicode_literals)

import os.path
import sys
import datetime
import backtrader as bt

create a strategy

class TestStrategy(bt.Strategy):
def log(self, txt, dt=None):
dt = dt or self.datas[0].datetime.date(0)
print('%s, %s' % (dt.isoformat(), txt))

def __init__(self):
    self.dataclose = self.datas[0].close
    self.order = None

def notify_order(self, order):
    if order.status in [order.Submitted, order.Accepted]:
        return
    if order.status in [order.Completed]:
        if order.isbuy():
            self.log('Buy executed, %.2f' % order.executed.price)
        elif order.issell():
            self.lot('Sell executed, %.2f' % order.executed.price)
    elif order.status in [order.Canceld, order.Margin, order.Rejected]:
        self.log('Order Canceled/Margin/Rejected')
    self.order = None

def next(self):
    self.log('Close, %.2f' % self.dataclose[0])
    if self.order:
        return
    # check if we are in the market
    if not self.position:
        if self.dataclose[0] < self.dataclose[-1]:
            if self.dataclose[-1] < self.dataclose[-2]:
                self.log('BUY CREATE, %.2f' % self.dataclose[0])
                self.order = self.buy()
    else:
        # in market we might sell
        if len(self) >= (self.bar_executed + 5):
            self.log('Sell create, %.2f' % self.dataclose[0])

            self.order = self.sell()

if name == "main":
cerebro = bt.Cerebro()

# add a strategy
cerebro.addstrategy(TestStrategy)

modpath = os.path.dirname(os.path.abspath(sys.argv[0]))
datapath = os.path.join(modpath, 'datas/orcl-1995-2014.txt')
# create a data feed
data = bt.feeds.YahooFinanceCSVData(
    dataname=datapath, fromdate=datetime.datetime(2000, 1, 1),
    todate=datetime.datetime(2000, 12, 31), reverse=False)
# add datafeed to crerbro
cerebro.adddata(data)

# set out cash
cerebro.broker.setcash(100000.0)
# print out the starting conditions
print('starting portfolio value:%.2f' % cerebro.broker.getvalue())
# run over everthing
cerebro.run()

# print out the final result
print('Fianl Portfolio value:%.2f' % cerebro.broker.getvalue())

[xue]

from __future__ import (absolute_import, division,
                        print_function, unicode_literals)

import os.path
import sys
import datetime
import backtrader as bt


# create a strategy


class TestStrategy(bt.Strategy):
    def log(self, txt, dt=None):
        dt = dt or self.datas[0].datetime.date(0)
        print('%s, %s' % (dt.isoformat(), txt))

    def __init__(self):
        self.dataclose = self.datas[0].close
        self.order = None

    def notify_order(self, order):
        if order.status in [order.Submitted, order.Accepted]:
            return
        if order.status in [order.Completed]:
            if order.isbuy():
                self.log('Buy executed, %.2f' % order.executed.price)
            elif order.issell():
                self.lot('Sell executed, %.2f' % order.executed.price)
        elif order.status in [order.Canceld, order.Margin, order.Rejected]:
            self.log('Order Canceled/Margin/Rejected')
        self.order = None

    def next(self):
        self.log('Close, %.2f' % self.dataclose[0])
        if self.order:
            return
        # check if we are in the market
        if not self.position:
            if self.dataclose[0] < self.dataclose[-1]:
                if self.dataclose[-1] < self.dataclose[-2]:
                    self.log('BUY CREATE, %.2f' % self.dataclose[0])
                    self.order = self.buy()
        else:
            # in market we might sell
            if len(self) >= (self.bar_executed + 5):
                self.log('Sell create, %.2f' % self.dataclose[0])

                self.order = self.sell()


if __name__ == "__main__":
    cerebro = bt.Cerebro()

    # add a strategy
    cerebro.addstrategy(TestStrategy)

    modpath = os.path.dirname(os.path.abspath(sys.argv[0]))
    datapath = os.path.join(modpath, 'datas/orcl-1995-2014.txt')
    # create a data feed
    data = bt.feeds.YahooFinanceCSVData(
        dataname=datapath, fromdate=datetime.datetime(2000, 1, 1),
        todate=datetime.datetime(2000, 12, 31), reverse=False)
    # add datafeed to crerbro
    cerebro.adddata(data)

    # set out cash
    cerebro.broker.setcash(100000.0)
    # print out the starting conditions
    print('starting portfolio value:%.2f' % cerebro.broker.getvalue())
    # run over everthing
    cerebro.run()

    # print out the final result
    print('Fianl Portfolio value:%.2f' % cerebro.broker.getvalue())

[run-out]

@xue
The error is telling you that self.bar_exectued does not exist. You need to set the value of self.bar_exectued when the order is initially executed. You can do this in the notify_order method when the buy order is complete. Simply add in:

self.bar_executed = len(self)  

in the notify_order method. Like this:

def notify_order(self, order):
    if order.status in [order.Submitted, order.Accepted]:
        return
    if order.status in [order.Completed]:
        if order.isbuy():
            ####### HERE #########
            self.bar_executed = len(self)  
            self.log('Buy executed, %.2f' % order.executed.price)
        elif order.issell():
            self.lot('Sell executed, %.2f' % order.executed.price)
    elif order.status in [order.Canceld, order.Margin, order.Rejected]:
        self.log('Order Canceled/Margin/Rejected')
    self.order = None

[xue]

thank for your answer but also another problem meeted.

raceback (most recent call last):
  File "e:/trading/backtrader_ex/test.py", line 73, in <module>
    cerebro.run()
  File "e:\trading\backtrader_ex\backtrader\cerebro.py", line 1127, in run
    runstrat = self.runstrategies(iterstrat)
  File "e:\trading\backtrader_ex\backtrader\cerebro.py", line 1293, in runstrategies
    self._runonce(runstrats)
  File "e:\trading\backtrader_ex\backtrader\cerebro.py", line 1695, in _runonce
    strat._oncepost(dt0)
  File "e:\trading\backtrader_ex\backtrader\strategy.py", line 305, in _oncepost
    self._notify()
  File "e:\trading\backtrader_ex\backtrader\strategy.py", line 590, in _notify
    self.notify_order(order)
  File "e:/trading/backtrader_ex/test.py", line 30, in notify_order
    self.lot('Sell executed, %.2f' % order.executed.price)
  File "e:\trading\backtrader_ex\backtrader\lineseries.py", line 461, in __getattr__
    return getattr(self.lines, name)
AttributeError: 'Lines_LineSeries_LineIterator_DataAccessor_Strateg' object has no attribute 'lot'

[run-out]

@xue These two errors are really basic python errors you are making, not backtrader errors. You are being informed that self.lot doesn't exist, that's because your method is self.log.

 elif order.issell():
            self.lot('Sell executed, %.2f' % order.executed.price)

We are happy to help people learn backtrader, but we are not so eager to help people learn python. Take some time and practice some python tutorials, and when you improve a bit backtrader will easier for you to work with. Good luck!

[xue]

Sorry! the last error is not about python, it is a spell error

self.log(...)

is correct.
'''
set.lot(...)

is not correct.
thanks for you patient answer.