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Constant Amortized Time
... in simple terms:
If you do an operation say a million times, you don't really care about the worst-case or the best-case of that operation - what you care about is how much time is taken in total when you repeat the operation a million times.
So it doesn't matter if the operation is very slow onc...
How to check whether a pandas DataFrame is empty?
...[8]: len(df1.columns)
Out[8]: 0
In [9]: len(df2.columns)
Out[9]: 2
Critically, while the second dataframe df2 contains no data, it is not completely empty because it returns the amount of empty columns that persist.
Why it matters
Let's add a new column to these dataframes to understand the implic...
Add all files to a commit except a single file?
I have a bunch of files in a changeset, but I want to specifically ignore a single modified file. Looks like this after git status :
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How do I flush the PRINT buffer in TSQL?
...show up right away...',0,1) WITH NOWAIT
You shouldn't completely replace all your prints with raiserror. If you have a loop or large cursor somewhere just do it once or twice per iteration or even just every several iterations.
Also: I first learned about RAISERROR at this link, which I now cons...
Is unsigned integer subtraction defined behavior?
... not restricted to overflow of the upper bound of the type, and applies equally to values too low to be represented.
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One-liner to check whether an iterator yields at least one element?
... Similarly if you need to check if the iterator is empty, one could use all(False for _ in iterator) will check if the iterator is empty. (all returns True if the iterator is empty, otherwise it stops when it sees the first False element)
– KGardevoir
Apr 3 ...
Pros and cons of AppSettings vs applicationSettings (.NET app.config / Web.config)
... you cannot safely assume your number that you wanted to configure there really is a number - someone could put a string into that setting..... you just access it as ConfigurationManager["(key)"] and then it's up to you to know what you're dealing with.
Also, over time, the <appSettings> can...
How can I get the client's IP address in ASP.NET MVC?
I'm totally new to the ASP.NET MVC stack, and I was wondering what happened to the simple Page object and the Request ServerVariables object?
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C default arguments
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Not really. The only way would be to write a varargs function and manually fill in default values for arguments which the caller doesn't pass.
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What is the effect of extern “C” in C++?
...very compiler is required to provide "C" linkage
A linkage specification shall occur only in namespace scope
All function types, function names and variable names have a language linkage See Richard's Comment: Only function names and variable names with external linkage have a language linkage
Two ...