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Sort a list by multiple attributes?
...1], x[2]))
Or you can achieve the same using itemgetter (which is faster and avoids a Python function call):
import operator
s = sorted(s, key = operator.itemgetter(1, 2))
And notice that here you can use sort instead of using sorted and then reassigning:
s.sort(key = operator.itemgetter(1, 2)...
How can you do anything useful without mutable state?
I've been reading a lot of stuff about functional programming lately, and I can understand most of it, but the one thing I just can't wrap my head around is stateless coding. It seems to me that simplifying programming by removing mutable state is like "simplifying" a car by removing the dashboard:...
SQL Server CTE and recursion example
...le on it. This article shows employee info with the help of Sql server CTE and recursion. It is basically showing employees and their manager info. I am not able to understand how this query works. Here is the query:
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How can I profile C++ code running on Linux?
... a profiler, use one of the suggested ones.
However, if you're in a hurry and you can manually interrupt your program under the debugger while it's being subjectively slow, there's a simple way to find performance problems.
Just halt it several times, and each time look at the call stack. If there...
What is the difference between . (dot) and $ (dollar sign)?
What is the difference between the dot (.) and the dollar sign ($) ?
13 Answers
13
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What belongs in an educational tool to demonstrate the unwarranted assumptions people make in C/C++?
...e to prepare a little educational tool for SO which should help beginners (and intermediate) programmers to recognize and challenge their unwarranted assumptions in C, C++ and their platforms.
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ASP.NET Identity's default Password Hasher - How does it work and is it secure?
...her that is default implemented in the UserManager that comes with MVC 5 and ASP.NET Identity Framework, is secure enough? And if so, if you could explain to me how it works?
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What characters do I need to escape in XML documents?
... to escape all five characters in text. However, the three characters ", ' and > needn't be escaped in text:
<?xml version="1.0"?>
<valid>"'></valid>
Attributes
The safe way is to escape all five characters in attributes. However, the > character needn't be escaped in ...
How do I check if a string is a number (float)?
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Which, not only is ugly and slow
I'd dispute both.
A regex or other string parsing method would be uglier and slower.
I'm not sure that anything much could be faster than the above. It calls the function and returns. Try/Catch doesn't introd...
SQL Server Text type vs. varchar data type [closed]
I have variable length character data and want to store in SQL Server (2005) database. I want to learn some best practices about how to choose TEXT SQL type or choose VARCHAR SQL type, pros and cons in performance/footprint/function.
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