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Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?
...tutorial shows how branch prediction buffers work. The cache buffer is indexed by the lower portion of the address of the branch instruction. This works well unless two important uncorrelated branches share the same lower bits. In that case, you end-up with aliasing which causes many mispredicted ...
check if variable is dataframe
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Use isinstance, nothing else:
if isinstance(x, pd.DataFrame):
... # do something
PEP8 says explicitly that isinstance is the preferred way to check types
No: type(x) is pd.DataFrame
No: type(x) == pd.DataFrame
Yes: isinstance(x, pd.DataFrame)
And don't eve...
Deserializing JSON to .NET object using Newtonsoft (or LINQ to JSON maybe?)
I know there are a few posts about Newtonsoft so hopefully this isn't exactly a repeat...I'm trying to convert JSON data returned by Kazaa's API into a nice object of some kind
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Functional style of Java 8's Optional.ifPresent and if-not-Present?
...want to process it but what if I want to define the functionality and the execution will be then, check below enhancement;
public class OptionalConsumer<T> implements Consumer<Optional<T>> {
private final Consumer<T> c;
private final Runnable r;
public OptionalConsumer(Cons...
How do I make python wait for a pressed key?
...wait for a key press.
Additional info:
in Python 3 raw_input() does not exist
In Python 2 input(prompt) is equivalent to eval(raw_input(prompt))
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Create empty file using python [duplicate]
I'd like to create a file with path x using python. I've been using os.system(y) where y = 'touch %s' % (x) . I've looked for a non-directory version of os.mkdir , but I haven't been able to find anything. Is there a tool like this to create a file without opening it, or using system or popen/...
How to loop backwards in python? [duplicate]
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range() and xrange() take a third parameter that specifies a step. So you can do the following.
range(10, 0, -1)
Which gives
[10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
But for iteration, you should really be using xrange instead. So,
xrange...
\r\n, \r and \n what is the difference between them? [duplicate]
...r = CR (Carriage Return) → Used as a new line character in Mac OS before X
\n = LF (Line Feed) → Used as a new line character in Unix/Mac OS X
\r\n = CR + LF → Used as a new line character in Windows
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What does “|=” mean? (pipe equal operator)
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@A.R.S.: I can't think of a counter-example in Java (maybe if j is volatile?), but I'll take your word for it.
– David Schwartz
Jan 12 '13 at 17:10
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Python memoising/deferred lookup property decorator
Recently I've gone through an existing code base containing many classes where instance attributes reflect values stored in a database. I've refactored a lot of these attributes to have their database lookups be deferred, ie. not be initialised in the constructor but only upon first read. These attr...