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What is the real overhead of try/catch in C#?
... to make here:
Firstly, there is little or NO performance penalty in actually having try-catch blocks in your code. This should not be a consideration when trying to avoid having them in your application. The performance hit only comes into play when an exception is thrown.
When an exception is th...
How to list all users in a Linux group?
How do I list all members of a group in Linux (and possibly other unices)?
20 Answers
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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
How can I get last characters of a string
...the answer, using slice this way is also more performant: jsperf.com/slice-vs-substr-and-length
– theVinchi
Oct 20 '16 at 15:49
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How to count the frequency of the elements in an unordered list?
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nice, using groupby. I wonder about its efficiency vs. the dict approach, though
– Eli Bendersky
Jan 29 '10 at 12:20
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Forms authentication timeout vs sessionState timeout
...nger be authenticated—they will be redirected to the login page automatically. The slidingExpiration=true value is basically saying that as long as the user makes a request within the timeout value, they will continue to be authenticated (more details here). If you set slidingExpiration=false the ...
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
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Here's a small kmeans that uses any of the 20-odd distances in
scipy.spatial.distance, or a user function.
Comments would be welcome (this has had only one user so far, not enough);
in particular, what are your N, dim, k, metric ?
#!/u...
When should I use the Visitor Design Pattern? [closed]
...want to make the fewest possible modifications to it.
The Visitor pattern allows you to move each new operation in a suitable class, and you need to extend the hierarchy's interface only once. Let's do it. First, we define an abstract operation (the "Visitor" class in GoF) which has a method for ev...
用户界面（UI）组件 · App Inventor 2 中文网
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未指定 (unspecified)
查看 Android 开发者可能的完整列表的文档选项。
允许滚动
勾选（或设置真）后，屏幕上会出现一个垂直滚动条，应用程序高度能超出设备的物理高度。未选中时，应用程序高度...
Biggest advantage to using ASP.Net MVC vs web forms
... Test Driven Development" over any other method ? I'm also confused how it allows RESTful urls when HttpContext.RewritePath Method (String) has been around since .NET 2.0 ?
– Mark Broadhurst
Sep 9 '10 at 15:48
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