How to fix the code to work in HEX format?

Question

Help fix the code. My script sorts into even and odd numbers of coordinates in the list and only works with a list in decimal number format, but I need to fix the code to work with a list in HEX format (hexadecimal number format)

I don't know the Python language well, but I need to add function hex(str)

Here is a list like this List.txt

(0x52DF625,0x47A406E)
(0x3555F30,0x3323041)
(0x326A573,0x5A5E578)
(0x48F8EF7,0x98A4EF3)
(0x578FE62,0x331DF3E)
(0x3520CAD,0x1719BBB)
(0x506FC9F,0x40CF4A6)

Сode:

with open('List.txt') as fin,\
     open('Save+even.txt', 'a') as foutch,\
      open('Save-odd.txt', 'a') as foutnch:
    data = [line.strip() for line in fin]
    nch = [foutnch.write(str(i) + '\n') 
        for i in data if int(i[1:-1].split(',')[1]) % 2]
    ch = [foutch.write(str(i) + '\n') 
        for i in data if int(i[1:-1].split(',')[1]) % 2 != 1]

you have asked several questions here but you have never [accepted](https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work) an answer. please read up on [how to accept an answer](https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work), — hiro protagonist, May 22 '21 at 12:17
You might want to check out `contextlib.ExitStack()` to help clean up the `with` a bit. — JonSG, May 22 '21 at 13:46
@JonSG i did not know about [`ExitStack`](https://docs.python.org/3/library/contextlib.html#contextlib.ExitStack). thanks for bringing it up! i will hopefully remember it the next time i do something similar... — hiro protagonist, May 22 '21 at 14:14

hiro protagonist · Answer 1 · 2021-05-22T17:01:10.767

1

this may work for you (i used StringIO instead of real files - but added a comment on how you could use that with real files)

in_file = StringIO("""(0x52DF625,0x47A406E)
(0x3555F30,0x3323041)
(0x326A573,0x5A5E578)
(0x48F8EF7,0x98A4EF3)
(0x578FE62,0x331DF3E)
(0x3520CAD,0x1719BBB)
(0x506FC9F,0x40CF4A6)
""")

even_file = StringIO()
odd_file = StringIO()

# with open( "List.txt") as in_file, open("Save-even.txt", "w") as even_file, open("Save-odd.txt", "w") as odd_file:
for line in in_file:
    x_str, y_str = line.strip()[1:-1].split(",")
    x, y = int(x_str, 0), int(y_str, 0)
    if y & 1:  # y is odd
        odd_file.write(line)
    else:
        even_file.write(line)

print("odd")
print(odd_file.getvalue())

print("even")
print(even_file.getvalue())

it outputs:

odd
(0x3555F30,0x3323041)
(0x48F8EF7,0x98A4EF3)
(0x3520CAD,0x1719BBB)

even
(0x52DF625,0x47A406E)
(0x326A573,0x5A5E578)
(0x578FE62,0x331DF3E)
(0x506FC9F,0x40CF4A6)

the trick is to use base 0 when converting a hex string to int: int(x_str, 0),. see this answer.

edited May 22 '21 at 17:01

answered May 22 '21 at 12:05

hiro protagonist

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how do I put the list of the List.txt file since it weighs 1GB. And I would like to save the whole result in two files: 'Save + even.txt' / 'Save-odd.txt' – FOLBY May 22 '21 at 12:12
as stated in the comments: use the `for` loop inside this `with` statement: `with open( "List.txt") as in_file, open("Save-even.txt") as even_file, open("Save-odd.txt") as odd_file:` and get rid of all the `StringIO` stuff. that was just to make my example here self-contained. – hiro protagonist May 22 '21 at 12:14
oh, and the size of your input file it not an issue (well, 1GB should not be an issue on any reasonably recent hardware); i never read the file in entirely - i just iterate over the lines of it. – hiro protagonist May 22 '21 at 14:09
I did the same as you described, but I get an error: Traceback (most recent call last): File "D:/script.py", line 8, in even_file.write(line) io.UnsupportedOperation: not writable – FOLBY May 22 '21 at 14:36
How to describe code correctly? I am using python3. Like this https://pastebin.com/uuCn69HB – FOLBY May 22 '21 at 14:46
oh, my bad. you need to [`open`](https://docs.python.org/3/library/functions.html#open) the files you want to write to (as opposed to the one you only want to read from) with the mode `"w"`. updated in the answer – hiro protagonist May 22 '21 at 17:00
Thank you! May God grant you health! – FOLBY May 22 '21 at 18:26
you are welcome. but again: if the answer is helpful please [accept](https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work) it. – hiro protagonist May 23 '21 at 06:28

How to fix the code to work in HEX format?

1 Answers1