不能用Python中的完整路径写文件 [英] cannot write file with full path in Python

问题描述

我在Mac上使用Pandas，读取和写入CSV文件，奇怪的是，当使用完整路径，它有错误，当使用只是一个文件名，它的工作原理。我发布我的代码，工作和哪些不工作在我的意见下面，还有详细的错误消息。任何人都有好的想法？

  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'）＃不工作
 
回溯（最近一次调用）：
在< module>中的文件/Users/foo/PycharmProjects/DataWranglingTest/CSVTest1.py，第36行。 
 add_full_name（path_to_csv，path_to_new_csv）
文件/Users/foo/PycharmProjects/DataWranglingTest/CSVTest1.py，第28行，add_full_name 
 sourceDf.to_csv（'〜/ Downloads / newMaster。 csv'）
文件/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/frame.py ，第1189行，在to_csv 
 formatter.save（）
文件/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/ site-packages / pandas / core / format.py，行1442，保存
 encoding = self.encoding）
文件/usr/local/Cellar/python/2.7.8/Frameworks/Python .framework / Versions / 2.7 / lib / python2.7 / site-packages / pandas / core / common.py，第2831行，在_get_handle 
f = open（path，mode）
 IOError：[Errno 2]没有这样的文件或目录：'〜/ Downloads / newMaster.csv'
 
尝试使用前缀r，但不工作，
 
 path_to_csv = r'〜/下载/Master.csv'
 path_to_new_csv = r'〜/ Downloads / Master_new.csv'
 
文件/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/版本/ 2.7 / lib / python2.7 / site-packages / pandas / core / frame.py，行1189，in_csv 
 formatter.save（）
文件/ usr / local / Cellar / python / 2.7.8 / Frameworks / Python.framework / Versions / 2.7 / lib / python2.7 / site-packages / pandas / core / format.py，第1442行，保存
 encoding = self.encoding） 
文件/usr/local/Cellar/python/2.7.8/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pandas/core/common.py，第2831行，在_get_handle 
f = open（path，mode）
 IOError：[Errno 2]没有这样的文件或目录：'〜/ Downloads / Master_new.csv'
  
 
 
 
提前感谢，
 Lin 
解决方案
 p>尝试使用 os.path.join（）。
  import os 
（...）
 output_filename ='newMaster.csv'
 output_path = os.path.join（'Downloads'，output_filename）
 $ b sourceDf.to_csv（output_path）
  
使用相同的方法指向 .read_csv（）方向正确。
 
I am using Pandas on Mac, to read and write a CSV file, and the weird thing is when using full path, it has error and when using just a file name, it works. I post my code which works and which not works in my comments below, and also detailed error messages. Anyone have any good ideas?
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'
thanks in advance,
Lin
解决方案
Try using os.path.join().
import os
(...)
output_filename = 'newMaster.csv'
output_path = os.path.join('Downloads', output_filename)
(...)
sourceDf.to_csv(output_path)
Use the same methodology to point pandas.read_csv() in the right direction.

                        
这篇关于不能用Python中的完整路径写文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！