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How to override the [] operator in Python?
...
You need to use the __getitem__ method.
class MyClass:
def __getitem__(self, key):
return key * 2
myobj = MyClass()
myobj[3] #Output: 6
And if you're going to be setting values you'll need to implement the __setitem__ method too,...
Clearing NSUserDefaults
I'm using +[NSUserDefaults standardUserDefaults] to store application settings. This consists of roughly a dozen string values. Is it possible to delete these values permanently instead of just setting them to a default value?
...
List all indexes on ElasticSearch server?
...ise list of all indices in your cluster, call
curl http://localhost:9200/_aliases
this will give you a list of indices and their aliases.
If you want it pretty-printed, add pretty=true:
curl http://localhost:9200/_aliases?pretty=true
The result will look something like this, if your indices ...
How do I get the full path to a Perl script that is executing?
... if the script is at or below the CWD
Additionally, cwd(), getcwd() and abs_path() are provided by the Cwd module and tell you where the script is being run from
The module FindBin provides the $Bin & $RealBin variables that usually are the path to the executing script; this module also provides...
Convert a python 'type' object to a string
...
print type(someObject).__name__
If that doesn't suit you, use this:
print some_instance.__class__.__name__
Example:
class A:
pass
print type(A())
# prints <type 'instance'>
print A().__class__.__name__
# prints A
Also, it seems th...
Moving decimal places over in a double
...average introduce a greater error than multiplying by 0.01 once; but I'll happily concede @JasperBekkers's point about 100 being different, being exactly binary-representable.
– Amadan
Jan 12 '12 at 18:21
...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...e is the full assembly listing:
.file "a.cpp"
.section .text$_ZNKSt5ctypeIcE8do_widenEc,"x"
.linkonce discard
.align 2
LCOLDB0:
LHOTB0:
.align 2
.p2align 4,,15
.globl __ZNKSt5ctypeIcE8do_widenEc
.def __ZNKSt5ctypeIcE8do_widenEc; .scl 2; .type 32; .e...
Usage of __slots__?
What is the purpose of __slots__ in Python — especially with respect to when I would want to use it, and when not?
11 A...
What are Long-Polling, Websockets, Server-Sent Events (SSE) and Comet?
...s prior to HTML5 which use streaming and long-polling to achieve real time applications. Read more on wikipedia or this article.
Now, which one of them should I use for a realtime app (that I need to
code). I have been hearing a lot about websockets (with socket.io [a
node.js library]) but...
How do you calculate the average of a set of circular data? [closed]
...e, A, from a set of angle measurements
a[i] 0<=i
sum_i_from_1_to_N sin(a[i])
a = arctangent ---------------------------
sum_i_from_1_to_N cos(a[i])
The method given by starblue is computationally equivalent, but his reasons are clearer and probably program...