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Python exit commands - why so many and when should each be used?
...ution. The choices I've found are: quit() , exit() , sys.exit() , os._exit()
4 Answers
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How do I use IValidatableObject?
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class RangeIfTrueAttribute : RangeAttribute
{
private readonly string _NameOfBoolProp;
public RangeIfTrueAttribute(string nameOfBoolProp, int min, int max) : base(min, max)
{
_NameOfBoolProp = nameOfBoolProp;
}
public RangeIfTrueAttribute(string nameOfBoolProp, double ...
Getting distance between two points based on latitude/longitude
...4, and is implemented in geopy. For example,
import geopy.distance
coords_1 = (52.2296756, 21.0122287)
coords_2 = (52.406374, 16.9251681)
print geopy.distance.vincenty(coords_1, coords_2).km
will print the distance of 279.352901604 kilometers using the default ellipsoid WGS-84. (You can also ch...
Format a datetime into a string with milliseconds
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Useful with timezone too: date = datetime(2019,5,10) date_with_tz = pytz.timezone('Europe/Rome').localize(date) date_with_tz.isoformat(sep='T', timespec='milliseconds') output: '2019-05-10T00:00:00.000+02:00'
– Ena
May 10 '19 at 9:17
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Conveniently Declaring Compile-Time Strings in C++
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I haven't seen anything to match the elegance of Scott Schurr's str_const presented at C++ Now 2012. It does require constexpr though.
Here's how you can use it, and what it can do:
int
main()
{
constexpr str_const my_string = "Hello, world!";
static_assert(my_string.size() == 13,...
How to check whether a variable is a class or not?
...ou couldn't perform the check in the first place.
– a_guest
Dec 16 '16 at 12:42
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How can I access “static” class variables within class methods in Python?
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Why not just Foo.bar, instead of self.__class__.bar?
– mk12
Sep 13 '09 at 20:59
15
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Benchmarking (python vs. c++ using BLAS) and (numpy)
....1
Dot product benchmark
Code:
import numpy as np
a = np.random.random_sample((size,size))
b = np.random.random_sample((size,size))
%timeit np.dot(a,b)
Results:
System | size = 1000 | size = 2000 | size = 3000 |
netlib BLAS | 1350 ms | 10900 ms | 39200 ms | ...
Zip lists in Python
...x. list, string, tuple, dictionary)
Output (list)
1st tuple = (element_1 of numbers, element_1 of letters)
2nd tuple = (e_2 numbers, e_2 letters)
…
n-th tuple = (e_n numbers, e_n letters)
List of n tuples: n is the length of the shortest argument (input)
len(numbers) =...
How to reshape data from long to wide format
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@indra_patil - I would likely use the reshape2 package as indicated in one of the other answers. You could create a new question that's specific to your use case and post it if you can't figure it out.
– Chase...