python - 将 csv 文件读取到 python ValueError : could not convert string to float

Question

如有任何帮助，我们将不胜感激。请记住，我是 Python 的初学者。这是我遇到问题的代码部分:

__author__ = 'peter'



from datetime import datetime, timedelta
import csv


TICKER='CHTR'
STDEV_FILE = TICKER + '_stdev.csv'
TRADES_FILE = TICKER + '_trades.csv'
DATETIME_CSV_FORMAT = '%Y%m%d %H:%M:%S'

def read_data(csv_filename):
  result = {}
  with open(csv_filename, 'rb') as csvfile:
     reader = csv.reader(csvfile, delimiter=',', quotechar='|')
     header = reader.next()
     #print 'HEADER',header
     for row in reader:
        new_data=None
        if len(row)==6: # this is a QUOTES file
          ticker, date, time, price, rtn, standard = row
          rtn = float(rtn)
          standard = float(standard)
          new_data = [rtn, standard]
        else: # assume this is a TRADES file otherwise
          ticker, date, time, price, size = row
          price = float(price)
          size = int(size)
          new_data = [price, size]

        date_object = datetime.strptime(date +' '+time, DATETIME_CSV_FORMAT)
        if not ticker in result:
          result[ticker]=[]
        result[ticker].append([date_object] + new_data)
  return result

vol = read_data(STDEV_FILE)
trades = read_data(TRADES_FILE

)

当我运行它时，这是我收到的错误:

Traceback (most recent call last):
  File "/home/peter/PycharmProjects/Vol/Vol.py", line 39, in <module>
    vol = read_data(STDEV_FILE)
  File "/home/peter/PycharmProjects/Vol/Vol.py", line 25, in read_data
    standard = float(standard)
ValueError: could not convert string to float: #DIV/0!

我已经在其他 csv 文件上运行过，没有遇到任何问题。

这是 csv 文件的一个小样本:

SYMBOL  DATE    TIME    PRICE          RTN                     STDEV
-----------------------------------------------------------------------
CHTR    20130718    9:30:00 124.66  0                0
-----------------------------------------------------------------------
CHTR    20130718    9:30:00 124.66  0                0.0005674559
-----------------------------------------------------------------------
CHTR    20130718    9:30:00 124.56  -0.0008025039        0.0004539101
-----------------------------------------------------------------------
CHTR    20130718    9:30:00 124.54  -0.0001605781        0.0001135459
-----------------------------------------------------------------------
CHTR    20130718    9:30:00 124.54  0                0.0070177722
-----------------------------------------------------------------------
CHTR    20130718    9:31:56 123.310 -0.0099246286        0.011065531
-----------------------------------------------------------------------
CHTR    20130718    9:34:05 124.018 0.0057243955         0.0040363557
-----------------------------------------------------------------------

最终我想在 y 轴上绘制标准偏差，在 x 轴上绘制从午夜算起的秒数。任何帮助将不胜感激。

Answer 1

问题是您正在尝试将字符串“#DIV/0”转换为 float 。显然这是不可能的。原因是您试图在 excel/csv 工作表中的某处除以零。回头看看通过你的 excel 表，看看是否有任何东西被零除并改变它。

或者，您可以实现一个简单的 if 语句:

if standard == '#DIV/0':
    print 'Error'
else:
    standard = float(standard)

编辑:一些引用资料:http://office.microsoft.com/en-us/excel-help/correct-a-div-0-error-HP010066245.aspx