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__getattr__ on a module
How can implement the equivalent of a __getattr__ on a class, on a module?
8 Answers
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Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...code very difficult to read without goto as well. Like this one:
#define _ -F<00||--F-OO--;
int F=00,OO=00;main(){F_OO();printf("%1.3f\n",4.*-F/OO/OO);}F_OO()
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When is “i += x” different from “i = i + x” in Python?
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This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used for modifyi...
Using property() on classmethods
...te the property on the metaclass.
>>> class foo(object):
... _var = 5
... class __metaclass__(type): # Python 2 syntax for metaclasses
... pass
... @classmethod
... def getvar(cls):
... return cls._var
... @classmethod
... def setvar(cls, value):
.....
How to call asynchronous method from synchronous method in C#?
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Asynchronous programming does "grow" through the code base. It has been compared to a zombie virus. The best solution is to allow it to grow, but sometimes that's not possible.
I have written a few types in my Nito.AsyncEx library for dealing with a partially-asynchronous code base. There's no so...
How to use a dot “.” to access members of dictionary?
...ope to help you:
class Map(dict):
"""
Example:
m = Map({'first_name': 'Eduardo'}, last_name='Pool', age=24, sports=['Soccer'])
"""
def __init__(self, *args, **kwargs):
super(Map, self).__init__(*args, **kwargs)
for arg in args:
if isinstance(arg, dict...
Ignore python multiple return value
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One common convention is to use a "_" as a variable name for the elements of the tuple you wish to ignore. For instance:
def f():
return 1, 2, 3
_, _, x = f()
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How to set JVM parameters for Junit Unit Tests?
...on the fly also.
mvn test -DargLine="-Dsystem.test.property=test"
See http://www.cowtowncoder.com/blog/archives/2010/04/entry_385.html
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foll...
How to return a value from __init__ in Python?
I have a class with an __init__ function.
10 Answers
10
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Change column type from string to float in Pandas
...y what you want, but what if you wanted to save some memory and use a more compact dtype, like float32, or int8?
to_numeric() gives you the option to downcast to either 'integer', 'signed', 'unsigned', 'float'. Here's an example for a simple series s of integer type:
>>> s = pd.Series([1, 2...