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Naming convention - underscore in C++ and C# variables
... in a class field. What does the underscore mean? Is there a reference for all these special naming conventions?
19 Answers...
Get operating system info
...x]{2})', 'Windows');
// Doesn't seem like these are necessary...not totally sure though..
//$ros[] = array('(winnt)([0-9]{1,2}\.[0-9]{1,2}){0,1}', 'Windows NT');
//$ros[] = array('(windows nt)(([0-9]{1,2}\.[0-9]{1,2}){0,1})', 'Windows NT'); // fix by bg
$ros[] = array('Windows ME', '...
Why is it slower to iterate over a small string than a small list?
...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
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What do *args and **kwargs mean? [duplicate]
...r **kwargs as the last items in your function definition’s argument list allows that function to accept an arbitrary number of arguments and/or keyword arguments.
For example, if you wanted to write a function that returned the sum of all its arguments, no matter how many you supply, you could wr...
Can you find all classes in a package using reflection?
Is it possible to find all classes or interfaces in a given package? (Quickly looking at e.g. Package , it would seem like no.)
...
How are feature_importances in RandomForestClassifier determined?
...d in [1] (often cited, but unfortunately rarely read...). It is sometimes called "gini importance" or "mean decrease impurity" and is defined as the total decrease in node impurity (weighted by the probability of reaching that node (which is approximated by the proportion of samples reaching that no...
Calculating frames per second in a game
... mean the value of time that you calculated for the last frame. This way, all previous frames will be included, with the most recent frames weighted the most heavily.
– j_random_hacker
May 23 '13 at 20:37
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Django select only rows with duplicate field values
... syntax is also how Django interprets you wanting to do a join. So, essentially when you try to filter on that, Django thinks you're trying to do a join with count which obviously doesn't exist. The fix is to specify a name for your annotation result, i.e. annotate(mycount=Count('id')) and then filt...
What does $_ mean in PowerShell?
...
This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
What are the applications of binary trees?
...ningless - they are not a data structure, but a family of data structures, all with different performance characteristics. While it is true that unbalanced binary trees perform much worse than self-balancing binary trees for searching, there are many binary trees (such as binary tries) for which "b...