Replace multiple characters in a string

Question

Is there a simple way in python to replace multiples characters by another?

For instance, I would like to change:

name1_22:3-3(+):Pos_bos 


        

Answer 1

Use a translation table. In Python 2, maketrans is defined in the string module.

>>> import string
>>> table = string.maketrans("():", "___")

In Python 3, it is a str class method.

>>> table = str.maketrans("():", "___")

In both, the table is passed as the argument to str.translate.

>>> 'name1_22:3-3(+):Pos_bos'.translate(table)
'name1_22_3-3_+__Pos_bos'

---

In Python 3, you can also pass a single dict mapping input characters to output characters to maketrans:

table = str.maketrans({"(": "_", ")": "_", ":": "_"})

Answer 2

You could use re.sub to replace multiple characters with one pattern:

import re
s = 'name1_22:3-3(+):Pos_bos '
re.sub(r'[():]', '_', s)

Output

'name1_22_3-3_+__Pos_bos '

Answer 3

Another possibility is usage of so-called list comprehension combined with so-called ternary conditional operator following way:

text = 'name1_22:3-3(+):Pos_bos '
out = ''.join(['_' if i in ':)(' else i for i in text])
print(out) #name1_22_3-3_+__Pos_bos

As it gives list, I use ''.join to change list of characters (strs of length 1) into str.

Answer 4

Sticking to your current approach of using replace():

s =  "name1_22:3-3(+):Pos_bos"
for e in ((":", "_"), ("(", "_"), (")", "__")):
    s = s.replace(*e)
print(s)

OUTPUT:

name1_22_3-3_+___Pos_bos

EDIT: (for readability)

s =  "name1_22:3-3(+):Pos_bos"
replaceList =  [(":", "_"), ("(", "_"), (")", "__")]

for elem in replaceList:
    print(*elem)          # : _, ( _, ) __  (for each iteration)
    s = s.replace(*elem)
print(s)

OR

repList = [':','(',')']   # list of all the chars to replace
rChar = '_'               # the char to replace with
for elem in repList:
    s = s.replace(elem, rChar)
print(s)