Rearranging the order of a sequence such that the final order is a mirror image of the original.
Rearranging the order of a sequence such that the final order is a mirror image of the original.
Questions tagged [reverse]
3773 questions
1194
votes
9 answers
How do I sort a list of objects based on an attribute of the objects?
I have a list of Python objects that I want to sort by a specific attribute of each object:
[Tag(name="toe", count=10), Tag(name="leg", count=2), ...]
How do I sort the list by .count in descending order?
Nick Sergeant
- 35,843
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1036
votes
28 answers
Traverse a list in reverse order in Python
How do I traverse a list in reverse order in Python? So I can start from collection[len(collection)-1] and end in collection[0].
I also want to be able to access the loop index.
Joan Venge
- 315,713
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1017
votes
33 answers
Reverse / invert a dictionary mapping
Given a dictionary like so:
my_map = {'a': 1, 'b': 2}
How can one invert this map to get:
inv_map = {1: 'a', 2: 'b'}
Brian M. Hunt
- 81,008
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579
votes
56 answers
How do you reverse a string in-place in JavaScript?
How do you reverse a string in-place in JavaScript when it is passed to a function with a return statement, without using built-in functions (.reverse(), .charAt() etc.)?
Jake
508
votes
20 answers
Print a list in reverse order with range()?
How can you produce the following list with range() in Python?
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
ramesh.mimit
- 9,445
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472
votes
12 answers
JQuery .each() backwards
I'm using JQuery to select some elements on a page and then move them around in the DOM. The problem I'm having is I need to select all the elements in the reverse order that JQuery naturally wants to select them. For example:
- Item…
Jack Mills
- 6,022
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454
votes
7 answers
Python list sort in descending order
How can I sort this list in descending order?
timestamps = [
"2010-04-20 10:07:30",
"2010-04-20 10:07:38",
"2010-04-20 10:07:52",
"2010-04-20 10:08:22",
"2010-04-20 10:08:22",
"2010-04-20 10:09:46",
"2010-04-20…
Rajeev
- 44,985
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245
votes
12 answers
How to get a reversed list view on a list in Java?
I want to have a reversed list view on a list (in a similar way than List#sublist provides a sublist view on a list). Is there some function which provides this functionality?
I don't want to make any sort of copy of the list nor modify the list.
It…
Albert
- 65,406
- 61
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- 386
240
votes
7 answers
Right way to reverse a pandas DataFrame?
Here is my code:
import pandas as pd
data = pd.DataFrame({'Odd':[1,3,5,6,7,9], 'Even':[0,2,4,6,8,10]})
for i in reversed(data):
print(data['Odd'], data['Even'])
When I run this code, i get the following error:
Traceback (most recent call…
Michael
- 15,386
- 36
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231
votes
17 answers
angular ng-repeat in reverse
How can i get a reversed array in angular?
i'm trying to use orderBy filter, but it needs a predicate(e.g. 'name') to sort:
{{friend.name}}
{{friend.phone}}
…
Delremm
- 3,121
- 4
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- 13
193
votes
21 answers
How do you reverse a string in place in C or C++?
How do you reverse a string in C or C++ without requiring a separate buffer to hold the reversed string?
uvote
170
votes
15 answers
Can one do a for each loop in java in reverse order?
I need to run through a List in reverse order using Java.
So where this does it forwards:
for(String string: stringList){
//...do something
}
Is there some way to iterate the stringList in reverse order using the for each syntax?
For clarity: I…
Ron Tuffin
- 53,859
- 24
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- 78
169
votes
21 answers
How to read a file in reverse order?
How to read a file in reverse order using python? I want to read a file from last line to first line.
Nimmy
- 5,051
- 7
- 33
- 32
150
votes
35 answers
148
votes
19 answers
How do I exchange keys with values in a dictionary?
I receive a dictionary as input, and would like to to return a dictionary whose keys will be the input's values and whose value will be the corresponding input keys. Values are unique.
For example, say my input is:
a =…
Roee Adler
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