All Questions
7,089
questions
2095
votes
10
answers
1.5m
views
Why is it string.join(list) instead of list.join(string)?
This has always confused me. It seems like this would be nicer:
["Hello", "world"].join("-")
Than this:
"-".join(["Hello", "world"])
Is ...
- 100k
1186
votes
3
answers
3.8m
views
1174
votes
12
answers
2.2m
views
How to concatenate (join) items in a list to a single string
How do I concatenate a list of strings into a single string?
For example, given ['this', 'is', 'a', 'sentence'], how do I get "this-is-a-sentence"?
For handling a few strings in separate ...
- 118k
978
votes
14
answers
1.1m
views
Remove empty strings from a list of strings
I want to remove all empty strings from a list of strings in python.
My idea looks like this:
while '' in str_list:
str_list.remove('')
Is there any more pythonic way to do this?
- 9,801
892
votes
21
answers
723k
views
How to convert string representation of list to a list
I was wondering what the simplest way is to convert a string representation of a list like the following to a list:
x = '[ "A","B","C" , " D"]'
Even in cases ...
- 11.6k
890
votes
3
answers
992k
views
C# List<string> to string with delimiter
Is there a function in C# to quickly convert some collection to string and separate values with delimiter?
For example:
List<string> names --> string names_together = "John, Anna, Monica"
- 20k
871
votes
17
answers
1.9m
views
How to check if a string is a substring of items in a list of strings
How do I search for items that contain the string 'abc' in the following list?
xs = ['abc-123', 'def-456', 'ghi-789', 'abc-456']
The following checks if 'abc' is in the list, but does not detect 'abc-...
- 11.8k
732
votes
23
answers
588k
views
Java: convert List<String> to a join()d String
JavaScript has Array.join()
js>["Bill","Bob","Steve"].join(" and ")
Bill and Bob and Steve
Does Java have anything like this? I know I can cobble something ...
- 187k
704
votes
15
answers
868k
views
How would you make a comma-separated string from a list of strings?
What would be your preferred way to concatenate strings from a sequence such that between every two consecutive pairs a comma is added. That is, how do you map, for instance, ['a', 'b', 'c'] to 'a,b,c'...
- 13.8k
687
votes
16
answers
1.2m
views
How do I split a string into a list of characters?
How do I split a string into a list of characters? str.split does not work.
"foobar" → ['f', 'o', 'o', 'b', 'a', 'r']
- 7,881
680
votes
11
answers
1.1m
views
Alphabet range in Python
How do I create a list of alphabet characters, without doing it manually like this?
['a', 'b', 'c', 'd', ..., 'z']
- 7,389
651
votes
10
answers
2.0m
views
How do I split a string into a list of words?
How do I split a sentence and store each word in a list? e.g.
"these are words" ⟶ ["these", "are", "words"]
To split on other delimiters, see Split a ...
- 7,583
560
votes
14
answers
1.2m
views
How to initialize a list of strings (List<string>) with many string values
How is it possible to initialize (with a C# initializer) a list of strings? I have tried with the example below but it's not working.
List<string> optionList = new List<string>
{
"...
- 8,867
414
votes
15
answers
580k
views
Determine if string is in list in JavaScript
In SQL we can see if a string is in a list like so:
Column IN ('a', 'b', 'c')
What's a good way to do this in JavaScript? It's so clunky to do this:
if (expression1 || expression2 || str === 'a' || ...
- 49.6k
406
votes
3
answers
378k
views
Splitting on last delimiter in Python string?
What's the recommended Python idiom for splitting a string on the last occurrence of the delimiter in the string? example:
# instead of regular split
>> s = "a,b,c,d"
>> s.split(",")
>&...
user248237
386
votes
9
answers
541k
views
How can I convert each item in the list to string, for the purpose of joining them? [duplicate]
I need to join a list of items. Many of the items in the list are integer values returned from a function; i.e.,
myList.append(munfunc())
How should I convert the returned result to a string in ...
- 6,375
332
votes
5
answers
425k
views
string.join(list) on object array rather than string array
In Python, I can do:
list = ['a', 'b', 'c']
', '.join(list) # 'a, b, c'
However, if I have a list of objects and try to do the same thing:
class Obj:
def __str__(self):
return 'name'
...
- 84.2k
330
votes
3
answers
260k
views
str.startswith with a list of strings to test for
I'm trying to avoid using so many comparisons and simply use a list, but not sure how to use it with str.startswith:
if link.lower().startswith("js/") or link.lower().startswith("...
- 3,365
316
votes
7
answers
208k
views
Check if string ends with one of the strings from a list
What is the pythonic way of writing the following code?
extensions = ['.mp3','.avi']
file_name = 'test.mp3'
for extension in extensions:
if file_name.endswith(extension):
#do stuff
I ...
306
votes
15
answers
559k
views
Convert a list to a string in C#
How do I convert a list to a string in C#?
When I execute toString on a List object, I get:
System.Collections.Generic.List`1[System.String]
- 63.3k
269
votes
11
answers
392k
views
How can I convert comma separated string into a List<int> [duplicate]
string tags = "9,3,12,43,2"
List<int> TagIds = tags.Split(',');
This doesn't work cause the split method returns a string[]
- 5,846
258
votes
15
answers
377k
views
How do I check if there are duplicates in a flat list?
For example, given the list ['one', 'two', 'one'], the algorithm should return True, whereas given ['one', 'two', 'three'] it should return False.
- 6,145
253
votes
5
answers
512k
views
Split a string by a delimiter in Python
How to split this string where __ is the delimiter
MATCHES__STRING
To get an output of ['MATCHES', 'STRING']?
For splitting specifically on whitespace, see How do I split a string into a list of ...
- 33.5k
235
votes
20
answers
455k
views
Removing a list of characters in string
I want to remove characters in a string in python:
string.replace(',', '').replace("!", '').replace(":", '').replace(";", '')...
But I have many characters I have to remove. I thought about a list
...
- 4,269
221
votes
9
answers
111k
views
case-insensitive list sorting, without lowercasing the result?
I have a list of strings like this:
['Aden', 'abel']
I want to sort the items, case-insensitive.
So I want to get:
['abel', 'Aden']
But I get the opposite with sorted() or list.sort(), because ...
user975135
220
votes
9
answers
590k
views
What exactly does the .join() method do?
I'm pretty new to Python and am completely confused by .join() which I have read is the preferred method for concatenating strings.
I tried:
strid = repr(595)
print array.array('c', random.sample(...
- 13.1k
219
votes
12
answers
197k
views
Case insensitive 'in'
I love using the expression
if 'MICHAEL89' in USERNAMES:
...
where USERNAMES is a list.
Is there any way to match items with case insensitivity or do I need to use a custom method? Just ...
- 25.3k
208
votes
6
answers
573k
views
Find and replace string values in list [duplicate]
I got this list:
words = ['how', 'much', 'is[br]', 'the', 'fish[br]', 'no', 'really']
What I would like is to replace [br] with some fantastic value similar to <br /> and thus getting a new ...
- 25.7k
194
votes
19
answers
356k
views
Best way to concatenate List of String objects? [duplicate]
What is the best way to concatenate a list of String objects? I am thinking of doing this way:
List<String> sList = new ArrayList<String>();
// add elements
if (sList != null)
{
...
- 5,866
193
votes
14
answers
741k
views
How to convert a string with comma-delimited items to a list in Python?
How do you convert a string into a list?
Say the string is like text = "a,b,c". After the conversion, text == ['a', 'b', 'c'] and hopefully text[0] == 'a', text[1] == 'b'?
- 4,495
187
votes
3
answers
404k
views
Best way to convert list to comma separated string in java [duplicate]
I have Set<String> result & would like to convert it to comma separated string. My approach would be as shown below, but looking for other opinion as well.
List<String> slist = new ...
- 4,589
182
votes
9
answers
142k
views
Join a list of strings in python and wrap each string in quotation marks
I've got:
words = ['hello', 'world', 'you', 'look', 'nice']
I want to have:
'"hello", "world", "you", "look", "nice"'
What's the easiest way to do this with Python?
- 4,889
177
votes
4
answers
420k
views
Apply function to each element of a list [duplicate]
Suppose I have a list like:
mylis = ['this is test', 'another test']
How do I apply a function to each element in the list? For example, how do I apply str.upper to get:
['THIS IS TEST', 'ANOTHER ...
- 32.1k
169
votes
5
answers
268k
views
How can I order a List<string>?
I have this List<string>:
IList<string> ListaServizi = new List<string>();
How can I order it alphabetically and ascending?
- 47.7k
164
votes
18
answers
381k
views
Python: how to print range a-z?
1. Print a-n: a b c d e f g h i j k l m n
2. Every second in a-n: a c e g i k m
3. Append a-n to index of urls{hello.com/, hej.com/, ..., hallo.com/}: hello.com/a hej.com/b ... hallo.com/n
- 51.7k
163
votes
22
answers
347k
views
Create nice column output in python
I am trying to create a nice column list in python for use with commandline admin tools which I create.
Basicly, I want a list like:
[['a', 'b', 'c'], ['aaaaaaaaaa', 'b', 'c'], ['a', 'bbbbbbbbbb', '...
- 5,371
155
votes
5
answers
386k
views
Finding a substring within a list in Python [duplicate]
Background:
Example list: mylist = ['abc123', 'def456', 'ghi789']
I want to retrieve an element if there's a match for a substring, like abc
Code:
sub = 'abc'
print any(sub in mystring for mystring in ...
- 5,423
151
votes
9
answers
141k
views
Pandas DataFrame stored list as string: How to convert back to list
I have an n-by-m Pandas DataFrame df defined as follows. (I know this is not the best way to do it. It makes sense for what I'm trying to do in my actual code, but that would be TMI for this post so ...
- 6,489
146
votes
8
answers
356k
views
Using Python String Formatting with Lists
I construct a string s in Python 2.6.5 which will have a varying number of %s tokens, which match the number of entries in list x. I need to write out a formatted string. The following doesn't work, ...
- 5,490
140
votes
7
answers
399k
views
Convert string to List<string> in one line?
I have a string:
var names = "Brian,Joe,Chris";
Is there a way to convert this to a List<string> delimited by , in one line?
- 7,594
137
votes
1
answer
197k
views
Python: How to check a string for substrings from a list? [duplicate]
How can I check a string for substrings contained in a list, like in Check if a string contains an element from a list (of strings), but in Python?
- 1,373
129
votes
6
answers
253k
views
How do I convert a list into a string with spaces in Python?
How can I convert a list into a space-separated string in Python?
For example, I want to convert this list:
my_list = ["how", "are", "you"]
into the string "how are ...
- 1,403
127
votes
8
answers
206k
views
Confused about __str__ on list in Python [duplicate]
Coming from a Java background, I understand that __str__ is something like a Python version of toString (while I do realize that Python is the older language).
So, I have defined a little class along ...
- 3,115
119
votes
5
answers
695k
views
Get the first character of the first string in a list?
How would I get the first character from the first string in a list in Python?
It seems that I could use mylist[0][1:] but that does not give me the first character.
>>> mylist = []
>&...
- 4,264
112
votes
7
answers
131k
views
string.Join on a List<int> or other type
I want to turn an array or list of ints into a comma delimited string, like this:
string myFunction(List<int> a) {
return string.Join(",", a);
}
But string.Join only takes List<string&...
- 17k
107
votes
5
answers
134k
views
Python: find closest string (from a list) to another string
Let's say I have a string "Hello" and a list
words = ['hello', 'Hallo', 'hi', 'house', 'key', 'screen', 'hallo','question', 'Hallo', 'format']
How can I find the n words that are the closest to "...
- 4,269
104
votes
6
answers
190k
views
Scala check if element is present in a list
I need to check if a string is present in a list, and call a function which accepts a boolean accordingly.
Is it possible to achieve this with a one liner?
The code below is the best I could get:
...
- 1,304
96
votes
7
answers
96k
views
How slow is Python's string concatenation vs. str.join?
As a result of the comments in my answer on this thread, I wanted to know what the speed difference is between the += operator and ''.join()
So what is the speed comparison between the two?
- 50.5k
95
votes
16
answers
263k
views
Converting a String to a List of Words?
I'm trying to convert a string to a list of words using python. I want to take something like the following:
string = 'This is a string, with words!'
Then convert to something like this :
list = ['...
- 51.6k
95
votes
3
answers
63k
views
Converting a string representation of a list into an actual list object [duplicate]
I have a string that looks identical to a list, let's say:
fruits = "['apple', 'orange', 'banana']"
What would be the way to convert that to a list object?
- 3,959