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Is 'switch' faster than 'if'?
Is a switch statement actually faster than an if statement?
12 Answers
12
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Reloading module giving NameError: name 'reload' is not defined
...in Python 2, but not in Python 3, so the error you're seeing is expected.
If you truly must reload a module in Python 3, you should use either:
importlib.reload for Python 3.4 and above
imp.reload for Python 3.0 to 3.3 (deprecated since Python 3.4 in favour of importlib)
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HTML if image is not found
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If Default.jpg is not available you will end up in an endless loop. You should add a check if (this.src != 'Default.jpg')
– dehlen
Jul 7 '16 at 10:05
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How do you do a deep copy of an object in .NET? [duplicate]
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I've seen a few different approaches to this, but I use a generic utility method as such:
public static T DeepClone<T>(this T obj)
{
using (var ms = new MemoryStream())
{
var formatter = new BinaryFormatter();
formatter.Ser...
Check if a number has a decimal place/is a whole number
I am looking for an easy way in JavaScript to check if a number has a decimal place in it (in order to determine if it is an integer). For instance,
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Get all non-unique values (i.e.: duplicate/more than one occurrence) in an array
I need to check a JavaScript array to see if there are any duplicate values. What's the easiest way to do this? I just need to find what the duplicated values are - I don't actually need their indexes or how many times they are duplicated.
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How do you round a float to two decimal places in jruby
...rency, but be aware that using #round(precision) will not work as intended if you are trying to do this (3.round(2) #=> 3.0, not 3.00). To get this, check out the answer by Theo below.
– jaredsmith
May 19 '14 at 21:48
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How to tell if rails is in production?
...ails in production mode. It did and I got no errors. However how do I tell if it is in production mode? I tried a non-existent route, and I got a similar error page I did in development.
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Filtering a list based on a list of booleans
...3: 2.58 us per loop
>>> %timeit [i for (i, v) in zip(list_a, fil) if v] #winner
100000 loops, best of 3: 1.98 us per loop
>>> list_a = [1, 2, 4, 6]*100
>>> fil = [True, False, True, False]*100
>>> %timeit list(compress(list_a, fil)) #winner
10000 lo...
Fast check for NaN in NumPy
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This only catches inf or -inf if the input contains both, and it has problems if the input contains large but finite values that overflow when added together.
– user2357112 supports Monica
Aug 19 '13 at 19:28
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