Best way to invert string case

Question

I am learning python and doing an exercise:

Strings. Create a function that returns another string, similar to the input string, but with an inverted case. For example, entering “Mr. Ed” will result in “mR. ED” as the output string.

My code is:

name = 'Mr.Ed' name_list = [] for i in name: if i.isupper(): name_list.append(i.lower()) elif i.islower(): name_list.append(i.upper()) else: name_list.append(i) print ''.join(name_list) 

Is there a better way to solve this problem? My decision seems strange.

Answer 1

Your decision is perfect. You do not need three branches, because str.upper() will return str if the top is not applicable.

Using generator expressions, this can be reduced to:

 >>> name = 'Mr.Ed' >>> ''.join(c.lower() if c.isupper() else c.upper() for c in name) 'mR.eD' 

Answer 2

You can do this with name.swapcase() . Find string methods .

Answer 3

Just use the swapcase () method:

 name = "Mr.Ed" name = name.swapcase() 

Output: mR.eD

-> This is just a two-line code.

Explanation:

The swapcase () method returns a copy of the string in which all random characters have been replaced with a case.

Happy coding!

Answer 4

https://github.com/suryashekhawat/pythonExamples/blob/master/string_toggle.py

  def toggle(mystr): arr = [] for char in mystr: if char.upper() != char: char=char.upper() arr.append(char) else: char=char.lower() arr.append(char) return ''.join(map(str,arr)) user_input = raw_input() output = toggle(user_input) print output