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Are tuples more efficient than lists in Python?
...s much faster than assigning a list.
>>> def a():
... x=[1,2,3,4,5]
... y=x[2]
...
>>> def b():
... x=(1,2,3,4,5)
... y=x[2]
...
>>> import dis
>>> dis.dis(a)
2 0 LOAD_CONST 1 (1)
3 LOAD_CONST ...
How to print a percentage value in python?
...age floating point precision type:
>>> print "{0:.0%}".format(1./3)
33%
If you don't want integer division, you can import Python3's division from __future__:
>>> from __future__ import division
>>> 1 / 3
0.3333333333333333
# The above 33% example would could now be w...
Is it worth using Python's re.compile?
...
TriptychTriptych
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...
How to pad zeroes to a string?
...
Strings:
>>> n = '4'
>>> print(n.zfill(3))
004
And for numbers:
>>> n = 4
>>> print(f'{n:03}') # Preferred method, python >= 3.6
004
>>> print('%03d' % n)
004
>>> print(format(n, '03')) # python >= 2.6
004
>>> ...
List comprehension on a nested list?
...
332
Here is how you would do this with a nested list comprehension:
[[float(y) for y in x] for x ...
How can I check which version of Angular I'm using?
...26
Kabb5
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answered Apr 15 '13 at 14:35
TheHippoTheHippo...
Postgres NOT in array
...
137
SELECT COUNT(*) FROM "messages" WHERE NOT (3 = ANY (recipient_ids))
You can always negate WHE...
How Does Modulus Divison Work
... means:
27 / 16 = 1, remainder 11
=> 27 mod 16 = 11
Other examples:
30 / 3 = 10, remainder 0
=> 30 mod 3 = 0
35 / 3 = 11, remainder 2
=> 35 mod 3 = 2
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How to return a part of an array in Ruby?
...#=> nil
a[1, 2] #=> [ "b", "c" ]
a[1..3] #=> [ "b", "c", "d" ]
a[4..7] #=> [ "e" ]
a[6..10] #=> nil
a[-3, 3] #=> [ "c", "d", "e" ]
# special cases
a[5] ...
How to use php serialize() and unserialize()
...
173
A PHP array or object or other complex data structure cannot be transported or stored or otherwi...