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How do I get the row count of a pandas DataFrame?
...[0].count()", "len(data.index)"],
xlabel="data rows"
)
EDIT: As @Dan Allen noted in the comments len(df.index) and df[0].count() are not interchangeable as count excludes NaNs,
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Number of processors/cores in command line
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Make sure to nproc --all for all installed Processing Units. Without --all, nproc only shows Processing Units available to the current process. Read the man page for more details. MMV.
– JamesThomasMoon1979
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How to return a string value from a Bash function
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+1 @tomas-f : you have to be really careful on what you have in this function "getSomeString()" as having any code which will eventually echo will mean that you get incorrect return string.
– Mani
Sep 14 '12 at 16:38
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Why can I not push_back a unique_ptr into a vector?
...to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:
std::unique_ptr<int> ptr(new int(1));
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How to detect the end of loading of UITableView
...htafoya's comment is right. If you want this code to detect end of loading all data from source, it wouldn't, but that's not the original question. This code is for detecting when all cells that are meant to be visible are displayed. willDisplayCell: used here for smoother UI (single cell usually di...
iOS 7 parallax effect in my view controller
... to the orientation of the user’s device. For example, to emulate the parallax effect on the home screen, you can use the subclass UIInterpolationMotionEffect, as explained here and here, just with a few lines of code.
Objective-C:
// Set vertical effect
UIInterpolatingMotionEffect *verticalMoti...
How to call Stored Procedure in Entity Framework 6 (Code-First)?
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You can call a stored procedure in your DbContext class as follows.
this.Database.SqlQuery<YourEntityType>("storedProcedureName",params);
But if your stored procedure returns multiple result sets as your sample code, then you...
How do you create a daemon in Python?
...Sander Marechal's code sample is superior to the original, which was originally posted in 2004. I once contributed a daemonizer for Pyro, but would probably use Sander's code if I had to do it over.
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Implementing slicing in __getitem__
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The __getitem__() method will receive a slice object when the object is sliced. Simply look at the start, stop, and step members of the slice object in order to get the components for the slice.
>>> class C(object):
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How to get an absolute file path in Python
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Note: On most platforms, this is equivalent to calling the function normpath() as follows: normpath(join(os.getcwd(), path)). So if mydir/myfile.txt do not under os.getcwd(), the absolute path is not the real path.
– coanor
Nov 25 '14...