How to remove brackets and commas from an string input?

Question

I am using the latest version of python and my IDE is the latest version of pycharm. I am attempting to convert RLE or raw data to hexadecimal. An example of the raw input would be [3, 15, 6, 4]. I don't know how I would go about removing the commas and brackets so that I could convert the raw data to hexadecimal or if I even have to remove the commas and brackets to convert. Any help would be appreciated.

For the example I provided input: [3, 15, 6, 4] output: 3f64

If you remove the commas, how will you know where each number ends? — Barmar, Oct 13 '22 at 17:47
You can use `json.loads()` or `ast.literal_eval()` to convert that to a list of integers. — Barmar, Oct 13 '22 at 17:48
Could you specify the output that you want to get? At the moment I would interpret ‘31564‘. — ai2ys, Oct 13 '22 at 17:53
I'm not sure if I have to remove the commas to convert the data I'm just not sure how to go about converting the raw data to hexadecimal — Guhan Gnanam, Oct 13 '22 at 17:54
For the example of raw data I gave the output should be the hexadecimal 3f64 — Guhan Gnanam, Oct 13 '22 at 17:55
Do you want to convert the single elements to hexadecimal? The easiest would be showing what the output is that you want to achieve. — ai2ys, Oct 13 '22 at 17:56
essentially it needs to convert each individual number to its hexadecimal equivalent and then print them as a string all together — Guhan Gnanam, Oct 13 '22 at 17:56
Is the maximum possible value for single entries in the array `15`? — ai2ys, Oct 13 '22 at 18:04

score 0 · Answer 1 · answered Oct 13 '22 at 17:53

0

If the brackets are part of your string, you could make list of hexadecimal numbers by using

nums = [hex(element) for element in str[1:-1].split(',')]

answered Oct 13 '22 at 17:53

chugaister

63
5

Andreas Schott · Answer 2 · 2022-10-13T18:11:39.567

string = "[3, 15, 6, 4]"
list_of_numbers = string[1:-1].split(", ") # gives us list_of_numbers = ['3', '15', '6', '4']
output = ""
for number in list_of_numbers:
    output = output + hex(int(number))[2:] # we need to convert our number to an int and then to hex

output should be 3f64, you get rid of the brackets by selecting a substring with [1:-1] and then you get rid of the commas/spaces with the split command

ai2ys · Answer 3 · 2022-10-13T18:42:41.667

In case the input is an array of int values:

a = [3, 15, 6, 4]
b = ""
for v in a:
   b = f'{b}{v:x}'
print(f'0x{b}')

In case the input is a string containing also brackets and commas:

import re
s = "[3, 15, 6, 4]"
# remove brackets and spaces, or other characters if required
replaced = re.sub('[\[\] ]', '', s)
# split by comma
a = replaced.split(',')
b = ""
for v in a:
    b = f'{b}{int(v):x}'
print(f'0x{b}')

With string input using numpy:

import numpy as np
s = '[3, 15, 6, 4]'
# convert string to array of int values
a = np.fromstring(s[1:-1], dtype=int, sep=',')
# use built-in formatting option
b = np.array2string(
  a,
  separator='',
  formatter={'int': lambda x: f'{x:x}'}
)[1:-1]
print(f'0x{b}')

How to remove brackets and commas from an string input?

3 Answers3