How would I read only the first word of each line of a text file?

Question

I wanted to know how I could read ONLY the FIRST WORD of each line in a text file. I tried various codes and tried altering codes but can only manage to read whole lines from a

Answer 1

You should read one character at a time:

import string

QuizList = []
with open('Quizzes.txt','r') as f:
    for line in f:
        for i, c in enumerate(line):
            if c not in string.letters:
                print line[:i]
                break

Answer 2

l=[] with open ('task-1.txt', 'rt') as myfile:

for x in myfile:                
    l.append(x)

for i in l: print[i.split()[0] ]

Answer 3

I'd go for the str.split and similar approaches, but for completness here's one that uses a combination of mmap and re if you needed to extract more complicated data:

import mmap, re

with open('quizzes.txt') as fin:
    mf = mmap.mmap(fin.fileno(), 0, access=mmap.ACCESS_READ)
    wordlist = re.findall('^(\w+)', mf, flags=re.M)

Answer 4

Changed to a one-liner that's also more efficient with the strip as Jon Clements suggested in a comment.

with open('Quizzes.txt', 'r') as f:
    wordlist = [line.split(None, 1)[0] for line in f]

---

This is pretty irrelevant to your question, but just so the line.split(None, 1) doesn't confuse you, it's a bit more efficient because it only splits the line 1 time.

From the str.split([sep[, maxsplit]]) docs

If sep is not specified or is None, a different splitting algorithm is applied: runs of consecutive whitespace are regarded as a single separator, and the result will contain no empty strings at the start or end if the string has leading or trailing whitespace. Consequently, splitting an empty string or a string consisting of just whitespace with a None separator returns [].

' 1 2 3 '.split() returns ['1', '2', '3']

and

' 1 2 3 '.split(None, 1) returns ['1', '2 3 '].

Answer 5

You are using split at the wrong point, try:

for line in f:
    QuizList.append(line.split(None, 1)[0]) # add only first word

Answer 6

with Open(filename,"r") as f:
    wordlist = [r.split()[0] for r in f]