Randomly capitalize letters in string

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up vote
7
down vote

favorite

I want to randomly capitalize or lowercase each letter in a string. I'm new to working with strings in python, but I think because strings are immutable that I can't do the following:

i =0 
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 sentence[i] = sentence[i].lower()
 else:
 print("here1")
 sentence[i] = sentence[i].upper()
 i += 1
print ("new sentence = ", sentence)

And get the error: TypeError: 'str' object does not support item assignment

But then how else could I do this?

python python-3.x uppercase lowercase

share|improve this question

edited 12 mins ago

Konrad Rudolph

388k1007641015

asked 8 hours ago

user1045890

574

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Use another container, like a list, then create the string from that. Alternatively, create a new sting incrementally
  – juanpa.arrivillaga
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  You can always create a new String with randomized caps and small letters.
  – Mayank Porwal
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  Possible duplicate of How do I modify a single character in a string, in Python?
  – Sneftel
  2 hours ago
  

  
  
  
  

add a comment | 

up vote
7
down vote

favorite

I want to randomly capitalize or lowercase each letter in a string. I'm new to working with strings in python, but I think because strings are immutable that I can't do the following:

i =0 
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 sentence[i] = sentence[i].lower()
 else:
 print("here1")
 sentence[i] = sentence[i].upper()
 i += 1
print ("new sentence = ", sentence)

And get the error: TypeError: 'str' object does not support item assignment

But then how else could I do this?

python python-3.x uppercase lowercase

share|improve this question

edited 12 mins ago

Konrad Rudolph

388k1007641015

asked 8 hours ago

user1045890

574

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Use another container, like a list, then create the string from that. Alternatively, create a new sting incrementally
  – juanpa.arrivillaga
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  You can always create a new String with randomized caps and small letters.
  – Mayank Porwal
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  Possible duplicate of How do I modify a single character in a string, in Python?
  – Sneftel
  2 hours ago
  

  
  
  
  

add a comment | 

up vote
7
down vote

favorite

up vote
7
down vote

favorite

I want to randomly capitalize or lowercase each letter in a string. I'm new to working with strings in python, but I think because strings are immutable that I can't do the following:

i =0 
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 sentence[i] = sentence[i].lower()
 else:
 print("here1")
 sentence[i] = sentence[i].upper()
 i += 1
print ("new sentence = ", sentence)

And get the error: TypeError: 'str' object does not support item assignment

But then how else could I do this?

python python-3.x uppercase lowercase

share|improve this question

edited 12 mins ago

Konrad Rudolph

388k1007641015

asked 8 hours ago

user1045890

574

I want to randomly capitalize or lowercase each letter in a string. I'm new to working with strings in python, but I think because strings are immutable that I can't do the following:

i =0 
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 sentence[i] = sentence[i].lower()
 else:
 print("here1")
 sentence[i] = sentence[i].upper()
 i += 1
print ("new sentence = ", sentence)

And get the error: TypeError: 'str' object does not support item assignment

But then how else could I do this?

python python-3.x uppercase lowercase

python python-3.x uppercase lowercase

share|improve this question

edited 12 mins ago

Konrad Rudolph

388k1007641015

asked 8 hours ago

user1045890

574

share|improve this question

edited 12 mins ago

Konrad Rudolph

388k1007641015

asked 8 hours ago

user1045890

574

share|improve this question

share|improve this question

edited 12 mins ago

Konrad Rudolph

388k1007641015

edited 12 mins ago

Konrad Rudolph

388k1007641015

edited 12 mins ago

Konrad Rudolph

388k1007641015

388k1007641015

asked 8 hours ago

user1045890

574

asked 8 hours ago

user1045890

574

asked 8 hours ago

user1045890

574

574

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Use another container, like a list, then create the string from that. Alternatively, create a new sting incrementally
  – juanpa.arrivillaga
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  You can always create a new String with randomized caps and small letters.
  – Mayank Porwal
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  Possible duplicate of How do I modify a single character in a string, in Python?
  – Sneftel
  2 hours ago
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Use another container, like a list, then create the string from that. Alternatively, create a new sting incrementally
  – juanpa.arrivillaga
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  You can always create a new String with randomized caps and small letters.
  – Mayank Porwal
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  Possible duplicate of How do I modify a single character in a string, in Python?
  – Sneftel
  2 hours ago
  

  
  
  
  

Use another container, like a list, then create the string from that. Alternatively, create a new sting incrementally
– juanpa.arrivillaga
8 hours ago

Use another container, like a list, then create the string from that. Alternatively, create a new sting incrementally
– juanpa.arrivillaga
8 hours ago

You can always create a new String with randomized caps and small letters.
– Mayank Porwal
8 hours ago

You can always create a new String with randomized caps and small letters.
– Mayank Porwal
8 hours ago

3

3

Possible duplicate of How do I modify a single character in a string, in Python?
– Sneftel
2 hours ago

Possible duplicate of How do I modify a single character in a string, in Python?
– Sneftel
2 hours ago

add a comment | 

7 Answers
7

active

oldest

votes

up vote
15
down vote



accepted

You can use str.join with a generator expression like this:

from random import choice
sentence = 'Hello World'
print(''.join(choice((str.upper, str.lower))(c) for c in sentence))

Sample output:

heLlo WORLd

share|improve this answer

answered 8 hours ago

blhsing

23.7k41134

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
  – blhsing
  8 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  Nice.., thanks for telling me
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  @U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
  – timgeb
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @timgeb Oh i am right, wow, now i know :-)
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  @timgeb I stand corrected then. Thanks.
  – blhsing
  8 hours ago
  

  
  
  
  

 | 
show 1 more comment

up vote
5
down vote

Build a new string.

Here's a solution with little changes to your original code:

>>> import random
>>> 
>>> def randomcase(s):
...: result = ''
...: for c in s:
...: case = random.randint(0, 1)
...: if case == 0:
...: result += c.upper()
...: else:
...: result += c.lower()
...: return result
...:
...:
>>> randomcase('Hello Stackoverflow!')
>>> 'hElLo StaCkoVERFLow!'

edit: deleted my oneliners because I like blhsing's better.

share|improve this answer

answered 8 hours ago

timgeb

39.4k105278

add a comment | 

up vote
3
down vote

Just change the string implementation to a list implementation. As string is immutable, you cannot change the value inside the object. But Lists can be, So I've only changed that part of your code. And make note that there are much better ways to do this, Follow here

import random
sentence = "This is a test sentence" # Strings are immutable
i =0
new_sentence = # Lists are mutable sequences
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 new_sentence += sentence[i].lower() # append to the list
 else:
 print("here1")
 new_sentence += sentence[i].upper() # append to the list
 i += 1
print ("new sentence = ", new_sentence)

# to print as string
new_sent = ''.join(new_sentence)
print(new_sent)

share|improve this answer

edited 8 hours ago

answered 8 hours ago

Vineeth Sai

1,46211019

add a comment | 

up vote
2
down vote

sentence='quick test' 
print(''.join([char.lower() if random.randint(0,1) else char.upper() for char in word ]))

qUiCK TEsT

share|improve this answer

edited 8 hours ago

answered 8 hours ago

AILearning

149111

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  you can pass your list to ''join() for a more complete solution
  – Ev. Kounis
  8 hours ago
  

  
  
  
  

add a comment | 

up vote
1
down vote

You can do like below

char_list = 
for c in sentence:
 ucase = random.randint(0,1)
 print("case = ", case)
 if ucase:
 print("here1")
 char_list.append(c.upper())
 else:
 print("here0")
 char_list.append(c.lower())
print ("new sentence = ", ''.join(char_list))

share|improve this answer

answered 8 hours ago

ansu5555

1816

add a comment | 

up vote
-1
down vote

One way without involving python loop would be sending it to numpy and do vectorized operation over that. For example:

import numpy as np
def randomCapitalize(s):
 s = np.array(s, 'c').view('u1')
 t = np.random.randint(0, 2, len(s), 'u1') # Temporary array
 t *= s != 32 # ASCII 32 (i.e. space) should not be lowercased
 t *= 32 # Decrease ASCII by 32 to lowercase
 s -= t
 return s.view('S' + str(len(s)))[0]
randomCapitalize('hello world jfwojeo jaiofjowejfefjawivj a jofjawoefj')

which outputs:

b'HELLO WoRlD jFwoJEO JAioFjOWeJfEfJAWIvJ A JofjaWOefj'

This solution should be reasonably fast especially for long string. There are two limitations of this method:

• The input must be fully lower case. You can try .lower() it first but thats technically low efficient.




• It need special care for non-a-to-z character. In the example above, only space is handled

You can handle a lot more special characters at the same time by replacing

t *= s != 32

with

# using space, enter, comma, period as example
t *= np.isin(s, list(map(ord, ' n,.')), invert=True)

For example:

s = 'ascii table and description. ascii stands for american standard code for information interchange. computers can only understand numbers, so an ascii code is the numerical representation of a character such as'
randomCapitalize(s)

which outputs:

b'ascII tABLe AnD descRiptIOn. ascii sTaNds for AmEricAN stanDaRD codE FOr InForMAtION iNTeRCHaNge. ComPUtERS can onLY UNdersTand nUMBers, So An asCIi COdE IS tHE nuMERIcaL rEPrEsEnTATion Of a CHaractEr such as'

share|improve this answer

answered 8 hours ago

ZisIsNotZis

99211

add a comment | 

up vote
-2
down vote

Use random.choice:

from random import choice
s = 'Hello World'
print(''.join([choice((i.upper(),i.lower())) for i in s]))

Output (random so no specific one):

hELLo worLD

share|improve this answer

edited 8 hours ago

answered 8 hours ago

U9-Forward

7,5272730

add a comment | 

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7 Answers
7

active

oldest

votes

7 Answers
7

active

oldest

votes

active

oldest

votes

active

oldest

votes

up vote
15
down vote



accepted

You can use str.join with a generator expression like this:

from random import choice
sentence = 'Hello World'
print(''.join(choice((str.upper, str.lower))(c) for c in sentence))

Sample output:

heLlo WORLd

share|improve this answer

answered 8 hours ago

blhsing

23.7k41134

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
  – blhsing
  8 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  Nice.., thanks for telling me
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  @U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
  – timgeb
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @timgeb Oh i am right, wow, now i know :-)
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  @timgeb I stand corrected then. Thanks.
  – blhsing
  8 hours ago
  

  
  
  
  

 | 
show 1 more comment

up vote
15
down vote



accepted

You can use str.join with a generator expression like this:

from random import choice
sentence = 'Hello World'
print(''.join(choice((str.upper, str.lower))(c) for c in sentence))

Sample output:

heLlo WORLd

share|improve this answer

answered 8 hours ago

blhsing

23.7k41134

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
  – blhsing
  8 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  Nice.., thanks for telling me
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  @U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
  – timgeb
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @timgeb Oh i am right, wow, now i know :-)
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  @timgeb I stand corrected then. Thanks.
  – blhsing
  8 hours ago
  

  
  
  
  

 | 
show 1 more comment

up vote
15
down vote



accepted

up vote
15
down vote



accepted

You can use str.join with a generator expression like this:

from random import choice
sentence = 'Hello World'
print(''.join(choice((str.upper, str.lower))(c) for c in sentence))

Sample output:

heLlo WORLd

share|improve this answer

answered 8 hours ago

blhsing

23.7k41134

You can use str.join with a generator expression like this:

from random import choice
sentence = 'Hello World'
print(''.join(choice((str.upper, str.lower))(c) for c in sentence))

Sample output:

heLlo WORLd

share|improve this answer

answered 8 hours ago

blhsing

23.7k41134

share|improve this answer

share|improve this answer

answered 8 hours ago

blhsing

23.7k41134

answered 8 hours ago

blhsing

23.7k41134

answered 8 hours ago

blhsing

23.7k41134

23.7k41134

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
  – blhsing
  8 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  Nice.., thanks for telling me
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  @U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
  – timgeb
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @timgeb Oh i am right, wow, now i know :-)
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  @timgeb I stand corrected then. Thanks.
  – blhsing
  8 hours ago
  

  
  
  
  

 | 
show 1 more comment

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
  – blhsing
  8 hours ago
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  Nice.., thanks for telling me
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  @U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
  – timgeb
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @timgeb Oh i am right, wow, now i know :-)
  – U9-Forward
  8 hours ago
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  @timgeb I stand corrected then. Thanks.
  – blhsing
  8 hours ago
  

  
  
  
  

1

1

No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
– blhsing
8 hours ago

No, list comprehension would be slower because it would materialize all item values first to form a list before passing the list to join, resulting in more overhead in both time and memory. With a generator expression, the join method would be able to simply iterate through the generator output as the generator produces item values one by one.
– blhsing
8 hours ago

1

1

Nice.., thanks for telling me
– U9-Forward
8 hours ago

Nice.., thanks for telling me
– U9-Forward
8 hours ago

6

6

@U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
– timgeb
8 hours ago

@U9-Forward You are correct. join needs a list, so giving it a list in the first place is faster than giving it a generator. Authoritative reference.
– timgeb
8 hours ago

1

1

@timgeb Oh i am right, wow, now i know :-)
– U9-Forward
8 hours ago

@timgeb Oh i am right, wow, now i know :-)
– U9-Forward
8 hours ago

2

2

@timgeb I stand corrected then. Thanks.
– blhsing
8 hours ago

@timgeb I stand corrected then. Thanks.
– blhsing
8 hours ago

 | 
show 1 more comment

up vote
5
down vote

Build a new string.

Here's a solution with little changes to your original code:

>>> import random
>>> 
>>> def randomcase(s):
...: result = ''
...: for c in s:
...: case = random.randint(0, 1)
...: if case == 0:
...: result += c.upper()
...: else:
...: result += c.lower()
...: return result
...:
...:
>>> randomcase('Hello Stackoverflow!')
>>> 'hElLo StaCkoVERFLow!'

edit: deleted my oneliners because I like blhsing's better.

share|improve this answer

answered 8 hours ago

timgeb

39.4k105278

add a comment | 

up vote
5
down vote

Build a new string.

Here's a solution with little changes to your original code:

>>> import random
>>> 
>>> def randomcase(s):
...: result = ''
...: for c in s:
...: case = random.randint(0, 1)
...: if case == 0:
...: result += c.upper()
...: else:
...: result += c.lower()
...: return result
...:
...:
>>> randomcase('Hello Stackoverflow!')
>>> 'hElLo StaCkoVERFLow!'

edit: deleted my oneliners because I like blhsing's better.

share|improve this answer

answered 8 hours ago

timgeb

39.4k105278

add a comment | 

up vote
5
down vote

up vote
5
down vote

Build a new string.

Here's a solution with little changes to your original code:

>>> import random
>>> 
>>> def randomcase(s):
...: result = ''
...: for c in s:
...: case = random.randint(0, 1)
...: if case == 0:
...: result += c.upper()
...: else:
...: result += c.lower()
...: return result
...:
...:
>>> randomcase('Hello Stackoverflow!')
>>> 'hElLo StaCkoVERFLow!'

edit: deleted my oneliners because I like blhsing's better.

share|improve this answer

answered 8 hours ago

timgeb

39.4k105278

Build a new string.

Here's a solution with little changes to your original code:

>>> import random
>>> 
>>> def randomcase(s):
...: result = ''
...: for c in s:
...: case = random.randint(0, 1)
...: if case == 0:
...: result += c.upper()
...: else:
...: result += c.lower()
...: return result
...:
...:
>>> randomcase('Hello Stackoverflow!')
>>> 'hElLo StaCkoVERFLow!'

edit: deleted my oneliners because I like blhsing's better.

share|improve this answer

answered 8 hours ago

timgeb

39.4k105278

share|improve this answer

share|improve this answer

answered 8 hours ago

timgeb

39.4k105278

answered 8 hours ago

timgeb

39.4k105278

answered 8 hours ago

timgeb

39.4k105278

39.4k105278

add a comment | 

add a comment | 

up vote
3
down vote

Just change the string implementation to a list implementation. As string is immutable, you cannot change the value inside the object. But Lists can be, So I've only changed that part of your code. And make note that there are much better ways to do this, Follow here

import random
sentence = "This is a test sentence" # Strings are immutable
i =0
new_sentence = # Lists are mutable sequences
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 new_sentence += sentence[i].lower() # append to the list
 else:
 print("here1")
 new_sentence += sentence[i].upper() # append to the list
 i += 1
print ("new sentence = ", new_sentence)

# to print as string
new_sent = ''.join(new_sentence)
print(new_sent)

share|improve this answer

edited 8 hours ago

answered 8 hours ago

Vineeth Sai

1,46211019

add a comment | 

up vote
3
down vote

Just change the string implementation to a list implementation. As string is immutable, you cannot change the value inside the object. But Lists can be, So I've only changed that part of your code. And make note that there are much better ways to do this, Follow here

import random
sentence = "This is a test sentence" # Strings are immutable
i =0
new_sentence = # Lists are mutable sequences
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 new_sentence += sentence[i].lower() # append to the list
 else:
 print("here1")
 new_sentence += sentence[i].upper() # append to the list
 i += 1
print ("new sentence = ", new_sentence)

# to print as string
new_sent = ''.join(new_sentence)
print(new_sent)

share|improve this answer

edited 8 hours ago

answered 8 hours ago

Vineeth Sai

1,46211019

add a comment | 

up vote
3
down vote

up vote
3
down vote

Just change the string implementation to a list implementation. As string is immutable, you cannot change the value inside the object. But Lists can be, So I've only changed that part of your code. And make note that there are much better ways to do this, Follow here

import random
sentence = "This is a test sentence" # Strings are immutable
i =0
new_sentence = # Lists are mutable sequences
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 new_sentence += sentence[i].lower() # append to the list
 else:
 print("here1")
 new_sentence += sentence[i].upper() # append to the list
 i += 1
print ("new sentence = ", new_sentence)

# to print as string
new_sent = ''.join(new_sentence)
print(new_sent)

share|improve this answer

edited 8 hours ago

answered 8 hours ago

Vineeth Sai

1,46211019

Just change the string implementation to a list implementation. As string is immutable, you cannot change the value inside the object. But Lists can be, So I've only changed that part of your code. And make note that there are much better ways to do this, Follow here

import random
sentence = "This is a test sentence" # Strings are immutable
i =0
new_sentence = # Lists are mutable sequences
for c in sentence:
 case = random.randint(0,1)
 print("case = ", case)
 if case == 0:
 print("here0")
 new_sentence += sentence[i].lower() # append to the list
 else:
 print("here1")
 new_sentence += sentence[i].upper() # append to the list
 i += 1
print ("new sentence = ", new_sentence)

# to print as string
new_sent = ''.join(new_sentence)
print(new_sent)

share|improve this answer

edited 8 hours ago

answered 8 hours ago

Vineeth Sai

1,46211019

share|improve this answer

share|improve this answer

edited 8 hours ago

edited 8 hours ago

edited 8 hours ago

answered 8 hours ago

Vineeth Sai

1,46211019

answered 8 hours ago

Vineeth Sai

1,46211019

answered 8 hours ago

Vineeth Sai

1,46211019

1,46211019

add a comment | 

add a comment | 

up vote
2
down vote

sentence='quick test' 
print(''.join([char.lower() if random.randint(0,1) else char.upper() for char in word ]))

qUiCK TEsT

share|improve this answer

edited 8 hours ago

answered 8 hours ago

AILearning

149111

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  you can pass your list to ''join() for a more complete solution
  – Ev. Kounis
  8 hours ago
  

  
  
  
  

add a comment | 

up vote
2
down vote

sentence='quick test' 
print(''.join([char.lower() if random.randint(0,1) else char.upper() for char in word ]))

qUiCK TEsT

share|improve this answer

edited 8 hours ago

answered 8 hours ago

AILearning

149111

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  you can pass your list to ''join() for a more complete solution
  – Ev. Kounis
  8 hours ago
  

  
  
  
  

add a comment | 

up vote
2
down vote

up vote
2
down vote

sentence='quick test' 
print(''.join([char.lower() if random.randint(0,1) else char.upper() for char in word ]))

qUiCK TEsT

share|improve this answer

edited 8 hours ago

answered 8 hours ago

AILearning

149111

sentence='quick test' 
print(''.join([char.lower() if random.randint(0,1) else char.upper() for char in word ]))

qUiCK TEsT

share|improve this answer

edited 8 hours ago

answered 8 hours ago

AILearning

149111

share|improve this answer

share|improve this answer

edited 8 hours ago

edited 8 hours ago

edited 8 hours ago

answered 8 hours ago

AILearning

149111

answered 8 hours ago

AILearning

149111

answered 8 hours ago

AILearning

149111

149111

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  you can pass your list to ''join() for a more complete solution
  – Ev. Kounis
  8 hours ago
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  you can pass your list to ''join() for a more complete solution
  – Ev. Kounis
  8 hours ago
  

  
  
  
  

1

1

you can pass your list to ''join() for a more complete solution
– Ev. Kounis
8 hours ago

you can pass your list to ''join() for a more complete solution
– Ev. Kounis
8 hours ago

add a comment | 

up vote
1
down vote

You can do like below

char_list = 
for c in sentence:
 ucase = random.randint(0,1)
 print("case = ", case)
 if ucase:
 print("here1")
 char_list.append(c.upper())
 else:
 print("here0")
 char_list.append(c.lower())
print ("new sentence = ", ''.join(char_list))

share|improve this answer

answered 8 hours ago

ansu5555

1816

add a comment | 

up vote
1
down vote

You can do like below

char_list = 
for c in sentence:
 ucase = random.randint(0,1)
 print("case = ", case)
 if ucase:
 print("here1")
 char_list.append(c.upper())
 else:
 print("here0")
 char_list.append(c.lower())
print ("new sentence = ", ''.join(char_list))

share|improve this answer

answered 8 hours ago

ansu5555

1816

add a comment | 

up vote
1
down vote

up vote
1
down vote

You can do like below

char_list = 
for c in sentence:
 ucase = random.randint(0,1)
 print("case = ", case)
 if ucase:
 print("here1")
 char_list.append(c.upper())
 else:
 print("here0")
 char_list.append(c.lower())
print ("new sentence = ", ''.join(char_list))

share|improve this answer

answered 8 hours ago

ansu5555

1816

You can do like below

char_list = 
for c in sentence:
 ucase = random.randint(0,1)
 print("case = ", case)
 if ucase:
 print("here1")
 char_list.append(c.upper())
 else:
 print("here0")
 char_list.append(c.lower())
print ("new sentence = ", ''.join(char_list))

share|improve this answer

answered 8 hours ago

ansu5555

1816

share|improve this answer

share|improve this answer

answered 8 hours ago

ansu5555

1816

answered 8 hours ago

ansu5555

1816

answered 8 hours ago

ansu5555

1816

1816

add a comment | 

add a comment | 

up vote
-1
down vote

One way without involving python loop would be sending it to numpy and do vectorized operation over that. For example:

import numpy as np
def randomCapitalize(s):
 s = np.array(s, 'c').view('u1')
 t = np.random.randint(0, 2, len(s), 'u1') # Temporary array
 t *= s != 32 # ASCII 32 (i.e. space) should not be lowercased
 t *= 32 # Decrease ASCII by 32 to lowercase
 s -= t
 return s.view('S' + str(len(s)))[0]
randomCapitalize('hello world jfwojeo jaiofjowejfefjawivj a jofjawoefj')

which outputs:

b'HELLO WoRlD jFwoJEO JAioFjOWeJfEfJAWIvJ A JofjaWOefj'

This solution should be reasonably fast especially for long string. There are two limitations of this method:

• The input must be fully lower case. You can try .lower() it first but thats technically low efficient.




• It need special care for non-a-to-z character. In the example above, only space is handled

You can handle a lot more special characters at the same time by replacing

t *= s != 32

with

# using space, enter, comma, period as example
t *= np.isin(s, list(map(ord, ' n,.')), invert=True)

For example:

s = 'ascii table and description. ascii stands for american standard code for information interchange. computers can only understand numbers, so an ascii code is the numerical representation of a character such as'
randomCapitalize(s)

which outputs:

b'ascII tABLe AnD descRiptIOn. ascii sTaNds for AmEricAN stanDaRD codE FOr InForMAtION iNTeRCHaNge. ComPUtERS can onLY UNdersTand nUMBers, So An asCIi COdE IS tHE nuMERIcaL rEPrEsEnTATion Of a CHaractEr such as'

share|improve this answer

answered 8 hours ago

ZisIsNotZis

99211

add a comment | 

up vote
-1
down vote

One way without involving python loop would be sending it to numpy and do vectorized operation over that. For example:

import numpy as np
def randomCapitalize(s):
 s = np.array(s, 'c').view('u1')
 t = np.random.randint(0, 2, len(s), 'u1') # Temporary array
 t *= s != 32 # ASCII 32 (i.e. space) should not be lowercased
 t *= 32 # Decrease ASCII by 32 to lowercase
 s -= t
 return s.view('S' + str(len(s)))[0]
randomCapitalize('hello world jfwojeo jaiofjowejfefjawivj a jofjawoefj')

which outputs:

b'HELLO WoRlD jFwoJEO JAioFjOWeJfEfJAWIvJ A JofjaWOefj'

This solution should be reasonably fast especially for long string. There are two limitations of this method:

• The input must be fully lower case. You can try .lower() it first but thats technically low efficient.




• It need special care for non-a-to-z character. In the example above, only space is handled

You can handle a lot more special characters at the same time by replacing

t *= s != 32

with

# using space, enter, comma, period as example
t *= np.isin(s, list(map(ord, ' n,.')), invert=True)

For example:

s = 'ascii table and description. ascii stands for american standard code for information interchange. computers can only understand numbers, so an ascii code is the numerical representation of a character such as'
randomCapitalize(s)

which outputs:

b'ascII tABLe AnD descRiptIOn. ascii sTaNds for AmEricAN stanDaRD codE FOr InForMAtION iNTeRCHaNge. ComPUtERS can onLY UNdersTand nUMBers, So An asCIi COdE IS tHE nuMERIcaL rEPrEsEnTATion Of a CHaractEr such as'

share|improve this answer

answered 8 hours ago

ZisIsNotZis

99211

add a comment | 

up vote
-1
down vote

up vote
-1
down vote

One way without involving python loop would be sending it to numpy and do vectorized operation over that. For example:

import numpy as np
def randomCapitalize(s):
 s = np.array(s, 'c').view('u1')
 t = np.random.randint(0, 2, len(s), 'u1') # Temporary array
 t *= s != 32 # ASCII 32 (i.e. space) should not be lowercased
 t *= 32 # Decrease ASCII by 32 to lowercase
 s -= t
 return s.view('S' + str(len(s)))[0]
randomCapitalize('hello world jfwojeo jaiofjowejfefjawivj a jofjawoefj')

which outputs:

b'HELLO WoRlD jFwoJEO JAioFjOWeJfEfJAWIvJ A JofjaWOefj'

This solution should be reasonably fast especially for long string. There are two limitations of this method:

• The input must be fully lower case. You can try .lower() it first but thats technically low efficient.




• It need special care for non-a-to-z character. In the example above, only space is handled

You can handle a lot more special characters at the same time by replacing

t *= s != 32

with

# using space, enter, comma, period as example
t *= np.isin(s, list(map(ord, ' n,.')), invert=True)

For example:

s = 'ascii table and description. ascii stands for american standard code for information interchange. computers can only understand numbers, so an ascii code is the numerical representation of a character such as'
randomCapitalize(s)

which outputs:

b'ascII tABLe AnD descRiptIOn. ascii sTaNds for AmEricAN stanDaRD codE FOr InForMAtION iNTeRCHaNge. ComPUtERS can onLY UNdersTand nUMBers, So An asCIi COdE IS tHE nuMERIcaL rEPrEsEnTATion Of a CHaractEr such as'

share|improve this answer

answered 8 hours ago

ZisIsNotZis

99211

One way without involving python loop would be sending it to numpy and do vectorized operation over that. For example:

import numpy as np
def randomCapitalize(s):
 s = np.array(s, 'c').view('u1')
 t = np.random.randint(0, 2, len(s), 'u1') # Temporary array
 t *= s != 32 # ASCII 32 (i.e. space) should not be lowercased
 t *= 32 # Decrease ASCII by 32 to lowercase
 s -= t
 return s.view('S' + str(len(s)))[0]
randomCapitalize('hello world jfwojeo jaiofjowejfefjawivj a jofjawoefj')

which outputs:

b'HELLO WoRlD jFwoJEO JAioFjOWeJfEfJAWIvJ A JofjaWOefj'

This solution should be reasonably fast especially for long string. There are two limitations of this method:

• The input must be fully lower case. You can try .lower() it first but thats technically low efficient.




• It need special care for non-a-to-z character. In the example above, only space is handled

You can handle a lot more special characters at the same time by replacing

t *= s != 32

with

# using space, enter, comma, period as example
t *= np.isin(s, list(map(ord, ' n,.')), invert=True)

For example:

s = 'ascii table and description. ascii stands for american standard code for information interchange. computers can only understand numbers, so an ascii code is the numerical representation of a character such as'
randomCapitalize(s)

which outputs:

b'ascII tABLe AnD descRiptIOn. ascii sTaNds for AmEricAN stanDaRD codE FOr InForMAtION iNTeRCHaNge. ComPUtERS can onLY UNdersTand nUMBers, So An asCIi COdE IS tHE nuMERIcaL rEPrEsEnTATion Of a CHaractEr such as'

share|improve this answer

answered 8 hours ago

ZisIsNotZis

99211

share|improve this answer

share|improve this answer

answered 8 hours ago

ZisIsNotZis

99211

answered 8 hours ago

ZisIsNotZis

99211

answered 8 hours ago

ZisIsNotZis

99211

99211

add a comment | 

add a comment | 

up vote
-2
down vote

Use random.choice:

from random import choice
s = 'Hello World'
print(''.join([choice((i.upper(),i.lower())) for i in s]))

Output (random so no specific one):

hELLo worLD

share|improve this answer

edited 8 hours ago

answered 8 hours ago

U9-Forward

7,5272730

add a comment | 

up vote
-2
down vote

Use random.choice:

from random import choice
s = 'Hello World'
print(''.join([choice((i.upper(),i.lower())) for i in s]))

Output (random so no specific one):

hELLo worLD

share|improve this answer

edited 8 hours ago

answered 8 hours ago

U9-Forward

7,5272730

add a comment | 

up vote
-2
down vote

up vote
-2
down vote

Use random.choice:

from random import choice
s = 'Hello World'
print(''.join([choice((i.upper(),i.lower())) for i in s]))

Output (random so no specific one):

hELLo worLD

share|improve this answer

edited 8 hours ago

answered 8 hours ago

U9-Forward

7,5272730

Use random.choice:

from random import choice
s = 'Hello World'
print(''.join([choice((i.upper(),i.lower())) for i in s]))

Output (random so no specific one):

hELLo worLD

share|improve this answer

edited 8 hours ago

answered 8 hours ago

U9-Forward

7,5272730

share|improve this answer

share|improve this answer

edited 8 hours ago

edited 8 hours ago

edited 8 hours ago

answered 8 hours ago

U9-Forward

7,5272730

answered 8 hours ago

U9-Forward

7,5272730

answered 8 hours ago

U9-Forward

7,5272730

7,5272730

add a comment | 

add a comment | 

 

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