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What does __FILE__ mean in Ruby?
... your require statements are at the top of your definitions (or at least before any calls to Dir.chdir), this value will continue to be useful after changing directories.
$MY_FILE_PATH = File.expand_path(File.dirname(__FILE__))
# open class and do some stuff that changes directory
puts $MY_FILE_P...
Are static class variables possible in Python?
...thod was invoked on, even if it's a subclass. A static method lacks this information, so it cannot call an overridden method, for example.
– Seb
Oct 2 '12 at 15:58
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What's the pythonic way to use getters and setters?
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Is the setter for x called in the initializer when instantiating _x?
– Casey
Jul 3 '19 at 15:12
7
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How to work with complex numbers in C?
...C? I see there is a complex.h header file, but it doesn't give me much information about how to use it. How to access real and imaginary parts in an efficient way? Is there native functions to get module and phase?
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Why prefer two's complement over sign-and-magnitude for signed numbers?
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It's done so that addition doesn't need to have any special logic for dealing with negative numbers. Check out the article on Wikipedia.
Say you have two numbers, 2 and -1. In your "intuitive" way of representing numbers, they would be 0010 and 1001, respectively (I'm sticking to 4 bits fo...
Python read-only property
... assumption that all users are consenting adults, and thus are responsible for using things correctly themselves. However, in the rare instance where it just does not make sense for an attribute to be settable (such as a derived value, or a value read from some static datasource), the getter-only p...
Checking if an instance's class implements an interface?
...xtension.
See: http://php.net/manual/en/function.class-implements.php
Performance Tests
Some simple performance tests show the costs of each approach:
Given an instance of an object
Object construction outside the loop (100,000 iterations)
____________________________________________
| class_...
Instance attribute attribute_name defined outside __init__
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The idea behind this message is for the sake of readability. We expect to find all the attributes an instance may have by reading its __init__ method.
You may still want to split initialization into other methods though. In such case, you can simply assign...
How to automatically generate a stacktrace when my program crashes
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For Linux and I believe Mac OS X, if you're using gcc, or any compiler that uses glibc, you can use the backtrace() functions in execinfo.h to print a stacktrace and exit gracefully when you get a segmentation fault. Documen...
Inverse dictionary lookup in Python
Is there any straightforward way of finding a key by knowing the value within a dictionary?
13 Answers
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