macOS Python Help

[citizensmith]

Hi,

I'm trying to learn Python. I'm working through a tutorial and I've hit a problem where I can't read anything from files. I get an error message saying no file or directory exists.

Heres my code:

# the open function returns a file object
file = open('Users/jamie/Python/German.txt', 'rb')

# loop over each line of the file
for line in file:
print line

# releases the file object

file.close()


Any help would be great!

Thanks

 

[iMeowbot]

This line:

file = open('Users/jamie/Python/German.txt', 'rb')

needs a leading slash to be a full path:

file = open('/Users/jamie/Python/German.txt', 'rb')

Without the leading slash, it's trying to find all that beneath your current working directory.

 

[citizensmith]

Ah great thanks!

I've only just switched to Mac so I'm still getting to grips with the file system.

Sorry for the uber noob question!

 

[iMeowbot]

Yep, it's all obvious, after you know

You can use os.path.realpath to get a better feel for how these things happen. Try these from the Python interactive prompt:

import os
print os.path.realpath('German.txt')
print os.path.realpath('Users/jamie/Python/German.txt')
print os.path.realpath('/Users/jamie/Python/German.txt')

 

[citizensmith]

Thats cool, so could I have written my code like this?

import os
file = open(os.path.realpath('German.txt'))

 

[iMeowbot]

If the file is on your working directory, you don't even need that much.

file = open('German.txt')

would be enough. The realpath stuff is just so you can see what Python is doing behind the scenes.

 

[citizensmith]

Ah right good stuff. I like the very little of this language I've played with. Much cleaner than Java.