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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...using? On the latest version, I get a KeyError when I try .loc[[nonexistent_label]].
– Dan Allan
Nov 6 '14 at 16:58
2
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Object of custom type as dictionary key
...
You need to add 2 methods, note __hash__ and __eq__:
class MyThing:
def __init__(self,name,location,length):
self.name = name
self.location = location
self.length = length
def __hash__(self):
return hash((self.name...
Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
...
Inherit docstrings in Python class inheritance
...out this a while ago, and a recipe was created. Check it out here.
"""
doc_inherit decorator
Usage:
class Foo(object):
def foo(self):
"Frobber"
pass
class Bar(Foo):
@doc_inherit
def foo(self):
pass
Now, Bar.foo.__doc__ == Bar().foo.__doc__ == Foo.foo.__doc__...
How to get name of exception that was caught in Python?
...rent ways to get the name of the class of the exception:
type(exception).__name__
exception.__class__.__name__
exception.__class__.__qualname__
e.g.,
try:
foo = bar
except Exception as exception:
assert type(exception).__name__ == 'NameError'
assert exception.__class__.__name__ == '...
Accessing class variables from a list comprehension in the class definition
...(1)]
... return Foo
...
>>> dis.dis(foo)
2 0 LOAD_BUILD_CLASS
1 LOAD_CONST 1 (<code object Foo at 0x10a436030, file "<stdin>", line 2>)
4 LOAD_CONST 2 ('Foo')
7 MAKE_FUNCTION ...
Create a custom event in Java
...else in the package
interface ThrowListener {
public void Catch();
}
/*_____________________________________________________________*/class Thrower {
//list of catchers & corresponding function to add/remove them in the list
List<ThrowListener> listeners = new ArrayList<ThrowLis...
Why is “if not someobj:” better than “if someobj == None:” in Python?
...r not ? This is done using the following algorithm :
If the object has a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, ...
How to get a complete list of object's methods and attributes?
...nts accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir function returns the keys in the __dict__ attribute, i.e. all the attributes accessible if the __getattr__ ...
How do you log all events fired by an element in jQuery?
...JQueryEventHandlersDebugHooks(bMonTrigger, bMonOn, bMonOff)
{
jQuery.fn.___getHookName___ = function()
{
// First, get object name
var sName = new String( this[0].constructor ),
i = sName.indexOf(' ');
sName = sName.substr( i, sName.indexOf('(')-i )...