Python: Data Getting

Question

Im trying to find out how to get certain data from a file in the easiest way possible. I have searched all over the internet but can't find anything. I want to be able to do this:

File.txt:

data1 = 1
data2 = 2

but i want to get only data1 like so,

p = open('file.txt')
f = p.get(data1)
print(f)

Any Ideas, Thanks in advance.

angvillar · Answer 1 · 2013-05-24T02:17:38.423

2

You can do:

with open("file.txt", "r") as f:
    for line in f:
        key, val = line.split('=')
        key = key.strip()
        val = val.strip() 
        if key == 'data1':  # if data1 is not the first line
            # do something with value and data

using map:

from operator import methodcaller
with open("file.txt", "r") as f:
    for line in f:
        key, val = map(methodcaller("strip", " "), line.split('='))
        if key == "data1":
             # do something with value and data

edited May 24 '13 at 02:17

answered May 24 '13 at 01:35

angvillar

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you just want to take data1 string? or the value of data1 or both? – angvillar May 24 '13 at 01:39
You might even just use `str.strip` rather than `methodcaller('strip')` if you can guarantee that `line.split` will return a list of `str` instances. – icktoofay May 24 '13 at 02:35

SethMMorton · Answer 2 · 2013-05-24T01:53:41.087

0

If you know you only want data1 which is on the first line, you can do

with open('file.txt', 'r') as f:
    key, val = tuple(x.strip() for x in f.readline().split('='))

The list comprehension is used to remove the whitespace from each string.

edited May 24 '13 at 01:53

answered May 24 '13 at 01:45

SethMMorton

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you can't call strip on a list object, think it causes and error. – angvillar May 24 '13 at 01:47
Yup, it does. I fixed that. Thanks – SethMMorton May 24 '13 at 01:48

kuafu · Accepted Answer · 2013-05-24T02:05:48.140

0

with open("file.txt", "r") as f:
        key, val = f.readline().split('=')
        if key.strip() == 'data1':  # if data1 is not the first line
            # do something with value and data

edited May 24 '13 at 02:05

answered May 24 '13 at 01:58

kuafu

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think that strip not removes the inner blank spaces so key == 'data1' fails cause it test key == 'data1 ' – angvillar May 24 '13 at 01:59
readline() just reads one line so if data1 is not in the first line you can retrieve it cause are not any iteration – angvillar May 24 '13 at 02:02
yes,you are right,but in the file maybe the user just want to the first line. – kuafu May 24 '13 at 02:06
the questions says that he wants to read data1 so to ensure that you can iterate over the lines of the file and check for the key – angvillar May 24 '13 at 02:09
in fact I think the data user want to read is a config file,so your map solution is better. – kuafu May 24 '13 at 02:26

Python: Data Getting

3 Answers3