Looping issues

[brochu121@gmail.com]

What I am trying to do is compare two files to each other.

If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:



correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")

for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."


correct_setting s.close()
current_setting s.close()


For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?

[anglozaxxon]

Re: Looping issues

On Apr 5, 2:01 pm, brochu...@gmail .com wrote:

What I am trying to do is compare two files to each other.
>
If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:
>
correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")
>
for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."
>
correct_setting s.close()
current_setting s.close()
>
For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?

Instead of "for line in correct_setting s", try "for line in
correct_setting s.readlines()".

[brochu121@gmail.com]

Re: Looping issues

On Apr 5, 2:18 pm, "anglozaxxo n" <anglozax...@gm ail.comwrote:

On Apr 5, 2:01 pm, brochu...@gmail .com wrote:
>
>
>

What I am trying to do is compare two files to each other.

>

If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:

>

correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")

>

for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."

>

correct_setting s.close()
current_setting s.close()

>

For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?

>
Instead of "for line in correct_setting s", try "for line in
correct_setting s.readlines()".

That Still didnt fix it. Same output

[Larry Bates]

Re: Looping issues

brochu121@gmail .com wrote:

What I am trying to do is compare two files to each other.
>
If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:
>
>
>
correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")
>
for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."
>
>
correct_setting s.close()
current_setting s.close()
>
>
For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?
>

If the files aren't terribly large (not tested):

correct_lines=o pen(r"C:\Python 25\Scripts\Outp ut" \
"\correct_setti ngs.txt", "r").readlines( )

current_lines=o pen(r"C:\Python 25\Scripts\Outp ut\output.txt",
"r").readlines( )

for line in current_setting s:
if line in correct_lines:
print line + " found"

This does what you asked for but somehow I don't think it is
what you want. I would suggest that you take a look at difflib.

Somththing along the lines of:

import difflib

correct_lines=o pen(r"C:\Python 25\Scripts\Outp ut" \
"\correct_setti ngs.txt", "r").readlines( )

current_lines=o pen(r"C:\Python 25\Scripts\Outp ut\output.txt",
"r").readlines( )

delta=difflib.u nified_diff(cor rect_lines, current_lines)
diffs=''.join(d elta)

print diffs

Will show you the lines that are different and some lines
around it for context.

-Larry

[Bruno Desthuilliers]

Re: Looping issues

anglozaxxon a écrit :

On Apr 5, 2:01 pm, brochu...@gmail .com wrote:
>

(snip)

>>For some reason this only looks at the first line of the
>>correct_setti ngs.txt file. Any ideas as to how i can loop through each
>>line of the correct_setting s file instead of just looking at the first?

>
>
Instead of "for line in correct_setting s", try "for line in
correct_setting s.readlines()".

What is this supposed to change ? (apart from loading the whole file in
memory, which may not be a problem here - config files are usually not
that big - but might become one for huge files...)

[anglozaxxon]

Re: Looping issues

On Apr 5, 2:27 pm, Larry Bates <larry.ba...@we bsafe.comwrote:

brochu...@gmail .com wrote:

What I am trying to do is compare two files to each other.

>

If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:

>

correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")

>

for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."

>

correct_setting s.close()
current_setting s.close()

>

For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?

>
If the files aren't terribly large (not tested):
>
correct_lines=o pen(r"C:\Python 25\Scripts\Outp ut" \
"\correct_setti ngs.txt", "r").readlines( )
>
current_lines=o pen(r"C:\Python 25\Scripts\Outp ut\output.txt",
"r").readlines( )
>
for line in current_setting s:
if line in correct_lines:
print line + " found"
>
This does what you asked for but somehow I don't think it is
what you want. I would suggest that you take a look at difflib.
>
Somththing along the lines of:
>
import difflib
>
correct_lines=o pen(r"C:\Python 25\Scripts\Outp ut" \
"\correct_setti ngs.txt", "r").readlines( )
>
current_lines=o pen(r"C:\Python 25\Scripts\Outp ut\output.txt",
"r").readlines( )
>
delta=difflib.u nified_diff(cor rect_lines, current_lines)
diffs=''.join(d elta)
>
print diffs
>
Will show you the lines that are different and some lines
around it for context.
>
-Larry

Sorry my solution didn't work. The only other thing I can think of is
that something is screwy with the newlines, although this seems
silly. I've heard Python has "universal newline" support, meaning \n
= \r = \r\n, etc.

Try printing the contents of the file in its entirety:
print current_setting s.read()
And see if it prints the entire file, or just the first line. I can't
imagine it won't print the whole thing. Next, do print
current_setting s.read().replac e('\\','\\\\'). This will make the
escape characters visible, so you can see exactly what type of
newlines it's printing. If the file is in Unix format and you're on
Windows, Python may be assuming the latter and not breaking lines
correctly. Post what it prints.

Nick

[Bruno Desthuilliers]

Re: Looping issues

brochu121@gmail .com a écrit :

What I am trying to do is compare two files to each other.
>
If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:
>
>
>
correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")
>
for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."
>
>
correct_setting s.close()
current_setting s.close()
>
>
For some reason this only looks at the first line of the
correct_setting s.txt file.

Not quite. It really go thru the whole file. But it only enter the inner
loop for the first line. Then the file iterator is exhausted, and the
other iterations are noop. You can verify this by adding a couple print
statements - one in the outer loop and one in the inner one.

Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?
>

The good question is "how to loop thru the lines of *current_*setti ngs
for each line of correct_setting s". The answer is : don't use the file
iterator here, read the whole file in memory. Cf Larry's post for a howto.

[hlubenow]

Re: Looping issues

brochu121@gmail .com wrote:

On Apr 5, 2:18 pm, "anglozaxxo n" <anglozax...@gm ail.comwrote:

>On Apr 5, 2:01 pm, brochu...@gmail .com wrote:
>>
>>
>>

What I am trying to do is compare two files to each other.

>>

If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:

>>

correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")

>>

for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."

>>

correct_setting s.close()
current_setting s.close()

>>

For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?

>>
>Instead of "for line in correct_setting s", try "for line in
>correct_settin gs.readlines()" .

>
That Still didnt fix it. Same output

Try this:

correct_setting s = file("C:\Python 25\Scripts\Outp ut\correct_sett ings.txt",
"r")
current_setting s = file("C:\Python 25\Scripts\Outp ut\output.txt", "r")

a = correct_setting s.readlines()
b = current_setting s.readlines()

correct_setting s.close()
current_setting s.close()

for line in a:
for val in b:
if val == line:
print line + " found."

[Peter Otten]

Re: Looping issues

Larry Bates wrote:

If the files aren't terribly large (not tested):
>
correct_lines=o pen(r"C:\Python 25\Scripts\Outp ut" \
                    "\correct_setti ngs.txt", "r").readlines( )
>
current_lines=o pen(r"C:\Python 25\Scripts\Outp ut\output.txt",
                    "r").readlines( )
>
for line in current_setting s:
    if line in correct_lines:
        print line + " found"

You only have to read the "inner" file into memory, and a set is more
efficient than a list here:

current_setting s = open(...)
correct_setting s = set(open(...))

for line in current_setting s:
if line in correct_setting s:
print line.rstrip(), "found"

Of course your suggestion of difflib is spot-on.

Peter

[thebjorn]

Re: Looping issues

On Apr 5, 8:01 pm, brochu...@gmail .com wrote:

What I am trying to do is compare two files to each other.
>
If the 2nd file contains the same line the first file contains, I want
to print it. I wrote up the following code:
>
correct_setting s = open("C:\Python 25\Scripts\Outp ut
\correct_settin gs.txt","r")
current_setting s = open("C:\Python 25\Scripts\Outp ut\output.txt", "r")
>
for line in correct_setting s:
for val in current_setting s:
if val == line:
print line + " found."
>
correct_setting s.close()
current_setting s.close()
>
For some reason this only looks at the first line of the
correct_setting s.txt file. Any ideas as to how i can loop through each
line of the correct_setting s file instead of just looking at the first?

I'm not entirely sure I understand what you're trying to do, but in
case you're trying to walk through the two files in lockstep printing
the lines that correspond, here's a way to do that:

# note the r'..' syntax
correct = open(r'c:\pytho n25\scripts\out put\correct_set tings.txt')
current = open(r'c:\pytho n25\scripts\out put\output.txt' )

for correct_line, current_line in zip(correct, current):
if correct_line == current_line:
print correct_line, 'found.'

correct.close()
current.close()

hth,
-- bjorn