Modify string line by line in Python

Question

I'm new to Python, I apologize if the question is simple. I have a string called decShow with this informartion:

 00:00:00,000 -> 94 FB
 00:00:00,100 -> 94 FA
 00:00:00,200 -> 94 F9
 00:00:00,300 -> 94 F8
 00:00:00,400 -> 94 F7
 00:00:00,500 -> 94 F6
 00:00:00,600 -> 94 F5
 00:00:00,700 -> 94 F4
 00:00:00,800 -> 94 F3
 00:00:00,900 -> 94 F2
 00:00:01,000 -> 94 F1
 00:00:01,100 -> 94 20

HH:MM:SS,sss -> Hex Code

I want to modify that string line by line, creating another string like this

00000000: Hex Code

where the zeros are a HEX value resulting from the conversion of each line minutes, seconds and miliseconds to miliseconds in hexadecimal. Maths are not the problem, the problem is the loop. After trying with a for line in decShow I'm not having the results I expected.

How can I efficiently do that?

EDIT: To clarify.

I have this in a string:

 00:00:00,000 -> 94 FB
 00:00:00,100 -> 94 FA
 00:00:00,200 -> 94 F9
 00:00:00,300 -> 94 F8

I want to transform it into this:

00000000: 94 FB
00000064: 94 FA
000000C8: 94 F9
0000012C: 94 F8

I tried a loop under for line in decShow but it seems it works just for .readlines()

Please provide a [mcve], it's unclear what you've tried, what the results were or how they differed from what you expected. — jonrsharpe, Jul 20 '18 at 13:13
Possible duplicate of [Split string using a newline delimiter with Python](https://stackoverflow.com/questions/22042948/split-string-using-a-newline-delimiter-with-python) — Ben Jones, Jul 20 '18 at 13:24

score 1 · Answer 1 · answered Jul 20 '18 at 13:21

1

You will need to split the string into line using str.splitlines() or .split('\n') and then strip out the characters that you dont want.

x = "\n".join([line.strip("->").strip(",") for line in decShow.splitlines()])

answered Jul 20 '18 at 13:21

Wamadahama

1,489
13
19

score 0 · Answer 2 · answered Jul 20 '18 at 13:18

0

for line in decShow treats decShow as a list of characters. You want to have a list of all the lines in decShow which is easily reachable using decShow.split("\n"), and then for line in decShow.split("\n") will give each line the value of a single line in decShow.

answered Jul 20 '18 at 13:18

Neo

3,534
2
20
32

(str.splitlines)[https://docs.python.org/2/library/stdtypes.html#str.splitlines] will be more robust here. – Ben Jones Jul 20 '18 at 13:22

score 0 · Answer 3 · answered Jul 20 '18 at 13:19

If decShow is a str, then your for loop will loop over characters, not lines. In order to loop over lines separated by newline characters, try using str.splitlines:

for line in decShow.splitlines():
    // convert line to your Hex representation here

score 0 · Answer 4 · answered Jul 20 '18 at 13:21

You can use decShow.split("\n") and it will split the string into multiple strings by the new line character. You can also use the same thing for example if you wanted to split that first part by commas decShow.split(",")

In addition, I think for this problem you're also going to need to do some substrings depending on how you go about it. You can read more about that elsewhere...

How to display the first few characters of a string in Python?

score 0 · Accepted Answer · answered Jul 20 '18 at 14:27

0

>>> import re
>>> tup_lst = [re.split(r' -> |,', l.strip()) for l in decShow.splitlines()]
>>> new_data = '\n'.join([a.replace(':', '')+'%03X: ' % int(b)+c for a,b,c in tup_lst])
>>> print (new_data)

Output

000000000: 94 FB
000000064: 94 FA
0000000C8: 94 F9
00000012C: 94 F8
000000190: 94 F7
0000001F4: 94 F6
000000258: 94 F5
0000002BC: 94 F4
000000320: 94 F3
000000384: 94 F2
000001000: 94 F1
000001064: 94 20

answered Jul 20 '18 at 14:27

Sunitha

11,777
2
20
23

All answers were useful, but this solution is by far the most efficient. Thank you very much. That really helped me, you learned me new things. – Lorum Jul 20 '18 at 20:34

Modify string line by line in Python

5 Answers5