Trying to manipulate a list of words in a textfile

[isakb]

Hi,

I am quite new to Python, and the following puzzles me, maybe there is someone here who can tell me what is wrong?

I have a list of words in a plain textfile (encoded in latin-1). There is one word per line, and 106299 words in total. I want to load the words to a list because I want to manipulate them, and then write them to a different file...

The mystery for me is that the new file only contains 106211 lines, even though I have not done anything with the list yet, and the last line contains a word that has been truncated.

I have tried many different version of the program, but this is the most basic one, and it gives the error mentioned above:

f = open("list.txt", "r")
wordlist = [w.lower() for w in f.readlines()]
f.close
 
f = open("new_list.txt", "w")
f.writelines(wordlist)
f.close
 

I am running this from Windows XP in Python 2.5.1, using IDLE.

[isakb]

An update: I was just told that IDLE is basically "useless" by a fellow programmer, so I tried running the script directly from the terminal instead of using IDLE. So this seems to be just an IDLE bug? (Sorry for not realizing that the results would differ, I thought IDLE used the same python as the terminal.)

[bvdet]

An update: I was just told that IDLE is basically "useless" by a fellow programmer, so I tried running the script directly from the terminal instead of using IDLE. So this seems to be just an IDLE bug? (Sorry for not realizing that the results would differ, I thought IDLE used the same python as the terminal.)

The problem is not with IDLE. You did not close the file. You must include '()' when closing the file.

f = open('file_name')
f.close()

The data is flushed through the buffer when the file is close. All the data was not written in your case.

[isakb]

Oh, thank you for that information. I also tried changing the buffering mode to none, which made it work in IDLE, so your explanation makes much sense. So I understand that you should always close a file after writing to it, but it is not necessary when reading from it?

[bvdet]

Oh, thank you for that information. I also tried changing the buffering mode to none, which made it work in IDLE, so your explanation makes much sense. So I understand that you should always close a file after writing to it, but it is not necessary when reading from it?

It is always a good idea to close every file that you open. Python takes care of garbage collection, so it is not a critical issue when reading the contents of a file as in:

data = open('file_name').read()

In this case, no file object is created.