how solve this error

[jack will]

Traceback (most recent call last):
File "D:/program/pycharm_code/stock_data_deal/双动量策略/部分数据测试/输出收盘价.py", line 62, in <module>
cerebro.run()
File "D:\program\Anaconda3\lib\site-packages\backtrader\cerebro.py", line 1127, in run
runstrat = self.runstrategies(iterstrat)
File "D:\program\Anaconda3\lib\site-packages\backtrader\cerebro.py", line 1212, in runstrategies
data.preload()
File "D:\program\Anaconda3\lib\site-packages\backtrader\feed.py", line 438, in preload
while self.load():
File "D:\program\Anaconda3\lib\site-packages\backtrader\feed.py", line 479, in load
_loadret = self._load()
File "D:\program\Anaconda3\lib\site-packages\backtrader\feeds\pandafeed.py", line 255, in _load
line[0] = self.p.dataname.iloc[self._idx, colindex]
File "D:\program\Anaconda3\lib\site-packages\backtrader\linebuffer.py", line 222, in setitem
self.array[self.idx + ago] = value
TypeError: must be real number, not str

my code:

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

import datetime  # For datetime objects
import os.path  # To manage paths
import sys  # To find out the script name (in argv[0])
import pandas as pd
# Import the backtrader platform
import backtrader as bt


# Create a Stratey
class TestStrategy(bt.Strategy):

    def log(self, txt, dt=None):
        ''' Logging function for this strategy'''  # 用了默认参数并用了短路原则，如果没有输入参数，就输出数据的日期，一个函数多用<br>        # 通过数据对象的属性方式取出线对象
        dt = dt or self.datas[0].datetime.date(0)# 生成ISO 8601日期
        print('%s, %s' % (dt.isoformat(), txt))

    def __init__(self):
        # Keep a reference to the "close" line in the data[0] dataseries<br>        # 一般情况下，通过self.datas[0]选出数据线集合的对象，通过属性选定指定的数据线，就是lines里面的一个对象
        self.dataclose = self.datas[0].close

    def next(self):
        # Simply log the closing price of the series from the reference<br>        # 这里将执行每个数据点位状态的输出，所以具体的逻辑后续也在这里写
        self.log('Close, %.2f' % self.dataclose[0])


if __name__ == '__main__':
    # Create a cerebro entity
    cerebro = bt.Cerebro()

    # Add a strategy
    cerebro.addstrategy(TestStrategy)
    dataframe = pd.read_csv('D:\program\pycharm_code\stock_data_deal\双动量策略\新数据\clean_ACWI.csv', index_col=0, parse_dates=True)
    # Datas are in a subfolder of the samples. Need to find where the script is
    # because it could have been called from anywhere
    # modpath = os.path.dirname(os.path.abspath(sys.argv[0]))
    # datapath = os.path.join(modpath, '../../datas/orcl-1995-2014.txt')
    dataframe['close'].astype('float')
    print(dataframe)
    # Create a Data Feed
    data = bt.feeds.PandasData(
        dataname=dataframe,
        # Do not pass values before this date
        fromdate=datetime.datetime(2011, 1, 1),
        # Do not pass values before this date
        todate=datetime.datetime(2011, 12, 31),
        # Do not pass values after this date
)

    # Add the Data Feed to Cerebro
    cerebro.adddata(data)

    # Set our desired cash start
    cerebro.broker.setcash(100000.0)

    # Print out the starting conditions
    print('Starting Portfolio Value: %.2f' % cerebro.broker.getvalue())

    # Run over everything
    cerebro.run()

    # Print out the final result
    print('Final Portfolio Value: %.2f' % cerebro.broker.getvalue())

i just want to output close,but fail,How can I solve this problem

[jack will]

           open  close     high      low    volume  openinterest  changes

date
2008-03-28 50.0999 50.10 50.1 50.0999 200 0 0.0000
2008-03-31 50.0000 49.32 50 49.32 400 0 -1.5569
2008-04-01 50.2500 50.65 50.65 50.16 584 0 2.6967
2008-04-02 51.1200 51.21 51.4 51.05 10699 0 1.0977
2008-04-03 59.7000 51.50 59.7 50.95 29013 0 0.5742
... ... ... ... ... ... ... ...

this is my data,I think it's all numerical

[Jonny8]

@jack-will

strange. Your code works for me with a different csv file.
I would assume that the csv file combined with that line is at fault:

dataframe['close'].astype('float')

Best

[run-out]

@jack-will said in how solve this error:

this is my data,I think it's all numerical

Just guessing but did you convert your date to datetime?

[jack will]

@Jonny8 thank you. i made this on purpose,If i delete this, it will still make an error