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Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...
Pragma in define macro
...ay of doing that. Then again, there are no portable ways to use #pragma at all. Because of this, many C/C++ compilers define their own methods for doing pragma-like things, and they often can be embedded in macros, but you need a different macro definition on every compiler. If you are willing to go...
Changing password with Oracle SQL Developer
... answered Feb 4 '13 at 22:21
NiallNiall
1,06911 gold badge77 silver badges33 bronze badges
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Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
Scala best way of turning a Collection into a Map-by-key?
...unction seems to assume that I already have a tuple (m,s), which I don't really get
– oxbow_lakes
Mar 24 '09 at 22:33
2
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How to find the operating system version using JavaScript?
...
If you list all of window.navigator's properties using
console.log(navigator);
You'll see something like this
# platform = Win32
# appCodeName = Mozilla
# appName = Netscape
# appVersion = 5.0 (Windows; en-US)
# language = en-US
# ...
Django ManyToMany filter()
...nes__in=[zone1, zone2, zone3])
The double underscore (__) syntax is used all over the place when working with querysets.
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What is a singleton in C#?
...
A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern i...
apt-get for Cygwin?
...
apt-cyg orks really well. Just installed rsync, openssh, mc and others.
– Jako
Feb 14 '13 at 0:51
9
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What does enumerate() mean?
...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function:
from itertools import count
def enumerate(it, start=0):
# return an iterator that adds a counter to each element of it
return zip(count(start), it)
and
def enumerate(it, sta...