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Do I set properties to nil in dealloc when using ARC?
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@zeiteisen: No. unsafe_unretained is exactly equivalent to an assign property and is the normal behavior for delegate relationships under MRR, and these need to be nilled out.
– Lily Ballard
Mar 7 '12 at 20:2...
Why is pow(a, d, n) so much faster than a**d % n?
... +1 that's actually what the docstring implies >>> print pow.__doc__ pow(x, y[, z]) -> number With two arguments, equivalent to x**y. With three arguments, equivalent to (x**y) % z, but may be more efficient (e.g. for longs).
– Hedde van der Heide
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Get bitcoin historical data [closed]
...ocket in higher resolution over longer time period you could use script log_bitstamp_trades.py below.
The script uses python websocket-client and pusher_client_python libraries, so install them.
#!/usr/bin/python
import pusherclient
import time
import logging
import sys
import datetime
import sig...
How to efficiently compare two unordered lists (not sets) in Python?
... objects are not unhashable per se. You just have to implements a sensible __hash__, but that might be impossible for collections.
– Jochen Ritzel
Oct 19 '11 at 22:23
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How do I uniquely identify computers visiting my web site?
...use the following keys on both document.cookie and window.localStorage:
_ga: Google Analytics data
__utma: Google Analytics tracking cookie
sid: SessionID
Make sure you include links to your Privacy policy and terms of use on all pages that use tracking.
Where do I store my session data?
You ...
Guava equivalent for IOUtils.toString(InputStream)
...se
CharStreams.toString(new InputStreamReader(supplier.get(), Charsets.UTF_8))
This code is problematic because the overload CharStreams.toString(Readable) states:
Does not close the Readable.
This means that your InputStreamReader, and by extension the InputStream returned by supplier.get(...
How can I split and parse a string in Python?
I am trying to split this string in python: 2.7.0_bf4fda703454
3 Answers
3
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round() for float in C++
...offers a simple set of rounding functions.
#include <boost/math/special_functions/round.hpp>
double a = boost::math::round(1.5); // Yields 2.0
int b = boost::math::iround(1.5); // Yields 2 as an integer
For more information, see the Boost documentation.
Edit: Since C++11, there are std::r...
Pythonic way to combine FOR loop and IF statement
...>>> xyz = [0, 12, 4, 6, 242, 7, 9]
>>>
>>> known_things = sorted(set(a.iterkeys()).intersection(xyz))
>>> unknown_things = sorted(set(xyz).difference(a.iterkeys()))
>>>
>>> for thing in known_things:
... print 'I know about', a[thing]
...
I k...
Are there any reasons to use private properties in C#?
... them if I need to cache a value and want to lazy load it.
private string _password;
private string Password
{
get
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
}
}
...