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Is using Random and OrderBy a good shuffle algorithm?
...dex];
elements[swapIndex] = elements[i];
}
}
This will now only do as much work as it needs to.
Note that in both cases, you need to be careful about the instance of Random you use as:
Creating two instances of Random at roughly the same time will yield the same sequence of ra...
When should iteritems() be used instead of items()?
....items() returned a list of (key, value) pairs. In Python 3.x, .items() is now an itemview object, which behaves different - so it has to be iterated over, or materialised... So, list(dict.items()) is required for what was dict.items() in Python 2.x.
Python 2.7 also has a bit of a back-port for key...
Proper way to renew distribution certificate for iOS
...l of my provisioning files. How do I properly renew it? Should I revoke it now and request a new one? If I do that than will all my live apps be taken down?
...
What does T&& (double ampersand) mean in C++11?
...bs Jul 13 '14 at 16:12
The biggest difference between a C++03 reference (now called an lvalue reference in C++11) is that it can bind to an rvalue like a temporary without having to be const. Thus, this syntax is now legal:
T&& r = T();
rvalue references primarily provide for the follo...
Anaconda vs. EPD Enthought vs. manual installation of Python [closed]
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Update 2015: Nowadays I always recommend Anaconda. It includes lots of Python packages for scientific computing, data science, web development, etc. It also provides a superior environment tool, conda, which allows to easily switch betwee...
Adding external library in Android studio
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I know it by experience and inspecting.... But there are docs available : developer.android.com/sdk/installing/studio-build.html
– malcubierre
Sep 2 '14 at 6:28
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JavaScript - get the first day of the week from current date
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Using the getDay method of Date objects, you can know the number of day of the week (being 0=Sunday, 1=Monday, etc).
You can then subtract that number of days plus one, for example:
function getMonday(d) {
d = new Date(d);
var day = d.getDay(),
diff = d.getDate()...
Difference between timestamps with/without time zone in PostgreSQL
...ly in the docs. The difference arises from what the system can reasonably know about the value:
With a time zone as part of the value, the value can be rendered as a local time in the client.
Without a time zone as part of the value, the obvious default time zone is UTC, so it is rendered for that...
How to make Git “forget” about a file that was tracked but is now in .gitignore?
There is a file that was being tracked by git , but now the file is on the .gitignore list.
27 Answers
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How to compare two dates?
...> from datetime import datetime, timedelta
>>> past = datetime.now() - timedelta(days=1)
>>> present = datetime.now()
>>> past < present
True
>>> datetime(3000, 1, 1) < present
False
>>> present - datetime(2000, 4, 4)
datetime.timedelta(4242, 757...