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How to deep copy a list?
...jects.
See the following snippet -
>>> a = [[1, 2, 3], [4, 5, 6]]
>>> b = list(a)
>>> a
[[1, 2, 3], [4, 5, 6]]
>>> b
[[1, 2, 3], [4, 5, 6]]
>>> a[0][1] = 10
>>> a
[[1, 10, 3], [4, 5, 6]]
>>> b # b changes too -> Not a deepcopy.
...
How to reshape data from long to wide format
...
268
Using reshape function:
reshape(dat1, idvar = "name", timevar = "numbers", direction = "wide")...
How do I find the duplicates in a list and create another list with them?
...
586
To remove duplicates use set(a). To print duplicates, something like:
a = [1,2,3,2,1,5,6,5,5,5]...
In STL maps, is it better to use map::insert than []?
...
– David Rodríguez - dribeas
Jan 4 '18 at 16:14
1
there is a way to tell if you inserted or just assigne...
Is there a “goto” statement in bash?
...$foo loops.)
– ruakh
Apr 28 '14 at 16:37
I'd recommend defining functions with the needed features and caling them fro...
How can I change UIButton title color?
..... :(
– Supertecnoboff
Jul 7 '15 at 6:40
How about with RGB ?
– Umit Kaya
Mar 1...
How do I look inside a Python object?
...
360
Python has a strong set of introspection features.
Take a look at the following built-in func...
Generating random numbers in Objective-C
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answered Oct 2 '08 at 16:00
lajoslajos
24.4k1919 gold badges6161 silver badges7474 bronze badges
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How do I check if a list is empty?
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5765
if not a:
print("List is empty")
Using the implicit booleanness of the empty list is quite ...
Where IN clause in LINQ [duplicate]
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263
This expression should do what you want to achieve.
dataSource.StateList.Where(s => country...