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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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How to create a printable Twitter-Bootstrap page
... type="text/css" media="print" href="print.css">
or one you share for all devices:
<link rel="stylesheet" type="text/css" href="bootstrap.min.css"> # Note there's no media attribute
Then, you can write your styles for printers in the separate stylesheets or in the shared one using medi...
Android: AsyncTask vs Service
... accomplish the same task with either an AsyncTask or a Service however usually one is better suited to a task than the other.
AsyncTasks are designed for once-off time-consuming tasks that cannot be run of the UI thread. A common example is fetching/processing data when a button is pressed.
Servi...
What exactly is a C pointer if not a memory address?
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The C standard does not define what a pointer is internally and how it works internally. This is intentional so as not to limit the number of platforms, where C can be implemented as a compiled or interpreted language.
A pointer value can be some kind of ID or handle or a combin...
Show SOME invisible/whitespace characters in Eclipse
A long while back I transitioned to doing all my web application development in Eclipse from BBEdit. But I miss one little feature from BBEdit. I used to be able to show invisible characters like tabs but not show other invisibles like spaces. I know that I can bulk turn all of these on in Eclipse, ...
How to use filter, map, and reduce in Python 3
... longer return lists:
[...]
map() and filter() return iterators. If you really need a list, a quick fix is e.g. list(map(...)), but a better fix is often to use a list comprehension (especially when the original code uses lambda), or rewriting the code so it doesn’t need a list at all. Particular...
Exporting data In SQL Server as INSERT INTO
...base, right-click and pick "Tasks" and then "Generate Scripts".
This will allow you to generate scripts for a single or all tables, and one of the options is "Script Data". If you set that to TRUE, the wizard will generate a script with INSERT INTO () statement for your data.
If using 2008 R2 or ...
How to exit from the application and show the home screen?
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will it dealocate all the resources? Because when I exit the app this way and after some time I click the app icon again. It starts from where I left it. That means the app was still running in the background.
– Adil Mali...
Detect if value is number in MySQL
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The accepted answer is really clever, but this answer is more direct, and I think it should be the accepted solution.
– pedromanoel
Oct 30 '13 at 15:50
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How can I get a count of the total number of digits in a number?
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@Puterdo Borato: my performance test actually showed that your method is faster when the number of digits are < 5. Pass that, Steve's Math.floor is faster.
– stack247
Apr 7 '15 at 22:56
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