How to capitalize each word of a given list of strings?

Question

I need to satisfy this test:

def test_capitalize_names():
    assert ["James"] == capitalize_names(["JAMES"])
    assert ["Harry", "Jack"] == capitalize_names(["HArry", "jack"])

I tried writing capitalize_names like so:

def capitalize_names(input):
    input = map(lambda s: s.capitalize(), input)
    li = map(lambda x: '"'+x+'"', input)
    return li

It is returning ['"James"'] but I want it to return ["James"] to satisfy the assert statements and I cannot use any control statements.

Don't use Python built-in keywords and function names as your variable names. Change `input` to something else. Also, check out https://stackoverflow.com/questions/1801668/convert-a-python-list-with-strings-all-to-lowercase-or-uppercase and many other similar questions is SO — Mazdak, Jun 23 '18 at 06:05
You can use `str.capitalize` instead of `lambda s: s.capitalize()`. — DYZ, Jun 23 '18 at 06:07
The line `li = map(lambda x: '"'+x+'"', my_input)` adds quotation marks to your capitalized string. Why are you surprised that the string has the quotation marks? Remove that line. From Python's point of view, `"` and `'` serve the same purpose. — DYZ, Jun 23 '18 at 06:08
But please read my comment. I said: use `str.capitalize` instead of `lambda s: s.capitalize()`. Just that: `my_input = map(str.capitalize, my_input)`. It makes your code 40% faster. Not using `map` (use list comprehension instead) makes it another 20% faster. — DYZ, Jun 23 '18 at 06:14
i removed that line and made it str.capitalize but now i want the code to satisfy assert the statement please help and thnk you for the suggestions — , Jun 23 '18 at 06:24
Did you try `["james"]==['james']`? The two lists (and strings) are exactly the same. — DYZ, Jun 23 '18 at 06:26
@marshmallow, for input like `['KEn watson']`, what do you expect? `['Ken Watson']` or `['Ken watson']`. — hygull, Jun 23 '18 at 07:36
The **original problem** here was **caused by a typo**. Questions should not be edited to ask a new question - the accepted answer was based on the code that I have restored in this edit. OP then edited to include the new working code and inappropriately ask a new question about getting a result `["James"]` rather than `['James']` - however, this **does not make sense**, because those **are the same thing** (and the `assert` would succeed in this case). Either way, there is not a reproducible problem in this question, and it should be closed and deleted. — Karl Knechtel, Mar 07 '23 at 21:23
For the question described in the title - which is **not what OP was asking** - we have many superior duplicates, anyway. — Karl Knechtel, Mar 07 '23 at 21:23

score 2 · Accepted Answer · answered Jun 23 '18 at 06:10

2

Try this:

def capitalize_names(input):
    return list(map(lambda s: s.capitalize(), input))

this is the efficient way of doing this.

answered Jun 23 '18 at 06:10

Mehrdad Pedramfar

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It is bad to use variable name as **input**. The statements like `m = input;` works perfect and gives ``. – hygull Jun 23 '18 at 06:50

U13-Forward · Answer 2 · 2018-06-23T07:28:07.030

1

The fastest way is:

def capitalize_names(inp):
    return [i.capitalize() for i in inp]
def test_capitalize_names():
    assert ["James"] == capitalize_names(["JAMES"])
    assert ["Harry", "Jack"] == capitalize_names(["HArry", "jack"])

edited Jun 23 '18 at 07:28

answered Jun 23 '18 at 06:08

U13-Forward

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This is the most efficient implementation (timewise). – DYZ Jun 23 '18 at 06:15
i cannot use any control statements – Jun 23 '18 at 06:28
@marshmallow What do you mean by control statements? – U13-Forward Jun 23 '18 at 06:45
1

@marshmallow My answer is much faster then mehrdad-pedramfar's answer – U13-Forward Jun 23 '18 at 06:47

score 1 · Answer 3 · answered Jun 23 '18 at 06:47

1

A more succinct way: for example:

import string
def capitalize_names(lst_str):
    return map(string.capitalize, lst_str)

if __name__ == '__main__':
    print capitalize_names(["HArry", "jack", "JAMES"])
    # ['Harry', 'Jack', 'James']

answered Jun 23 '18 at 06:47

Jayhello

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How to capitalize each word of a given list of strings?

3 Answers3