Question

我在Mac上使用Pandas，读取和写入一个CSV文件，奇怪的是当使用完整路径时，它有错误，当只使用文件名时，它可以工作。我发布了我的代码，该代码在我的评论中有效，哪些无效，还有详细的错误消息。有人有什么好主意吗？

sourceDf = pd.read_csv(path_to_csv)
sourceDf['nameFull'] = sourceDf['nameFirst'] + ' ' + sourceDf['nameLast']
sourceDf.to_csv('newMaster.csv') # working
sourceDf.to_csv('~/Downloads/newMaster.csv') # not working

Traceback (most recent call last):
  File "/Users/foo/PycharmProjects/DataWranglingTest/CSVTest1.py", line 36, in <module>
    add_full_name(path_to_csv, path_to_new_csv)
  File "/Users/foo/PycharmProjects/DataWranglingTest/CSVTest1.py", line 28, in add_full_name
    sourceDf.to_csv('~/Downloads/newMaster.csv')
  File "/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/frame.py", line 1189, in to_csv
    formatter.save()
  File "/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/format.py", line 1442, in save
    encoding=self.encoding)
  File "/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/common.py", line 2831, in _get_handle
    f = open(path, mode)
IOError: [Errno 2] No such file or directory: '~/Downloads/newMaster.csv'

Tried to use prefix r, but not working,

    path_to_csv = r'~/Downloads/Master.csv'
    path_to_new_csv = r'~/Downloads/Master_new.csv'

  File "/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/frame.py", line 1189, in to_csv
    formatter.save()
  File "/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/format.py", line 1442, in save
    encoding=self.encoding)
  File "/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/common.py", line 2831, in _get_handle
    f = open(path, mode)
IOError: [Errno 2] No such file or directory: '~/Downloads/Master_new.csv'

提前谢谢，林

Answer 1

尝试使用os.path.join()。

import os
(...)
output_filename = 'newMaster.csv'
output_path = os.path.join('Downloads', output_filename)
(...)
sourceDf.to_csv(output_path)

使用相同的方法将pandas.read_csv()指向正确的方向。

无法在Python

1 个答案: