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How do I get the row count of a pandas DataFrame?
...eturn non-NaN counts for each column:
df.count()
A 5
B 3
dtype: int64
For Series, use Series.count to similar effect:
s.count()
# 3
Group-wise Row Count: GroupBy.size
For DataFrames, use DataFrameGroupBy.size to count the number of rows per group.
df.groupby('A').size()
A
a 2
b ...
Integrated Markdown WYSIWYG text editor
...te, CKEditor now includes plugins that allow BBCode input and output.
A demo is available here: http://ckeditor.com/demo#bbcode
EDIT Apr 13, 2015:
Someone professing to develop CKEditor says that the appearance of CommonMark is a game changer, and we could possibly see a proper markup interface ...
AtomicInteger lazySet vs. set
...ite. There are a few
other use cases along these lines for non-reference-based
atomics as well, so the method is supported across all of the
AtomicX classes.
For people who like to think of these operations in terms of
machine-level barriers on common multiprocessors, lazySet
provides...
What is the difference between char array and char pointer in C?
...
gsamaras
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answered Apr 17 '12 at 7:15
JonJon
...
How can I open the interactive matplotlib window in IPython notebook?
...end(loc='best')
into a code cell (or just modify the existing python demo notebook)
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CMake: Project structure with unit tests
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How can I use PowerShell with the Visual Studio Command Prompt?
...nction will be available in the PowerShell Community Extensions 2.0 module-based release coming soon.
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汇编语言超浓缩教程（汇编入门必备） - C/C++ - 清泛网 - 专注C/C++及内核技术
...堆栈指针，与SS配合使用，可指向目前的堆栈位置。BP（Base Pointer）：基址指针寄存器，可用作SS的一个相对基址位置；SI（Source Index）：源变址寄存器可用来存放相对于DS段之源变址指针；DI（Destination Index）：目的变址寄存器，...
fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'X86'
...le it, I get the error message "fatal error LNK1112: module machine type 'x64' conflicts with target machine type 'X86'".
...
How do you make an element “flash” in jQuery
...eOut(100).fadeIn(100).fadeOut(100).fadeIn(100);
function go1() { $("#demo1").fadeOut(100).fadeIn(100).fadeOut(100).fadeIn(100)}
function go2() { $('#demo2').delay(100).fadeOut().fadeIn('slow') }
#demo1,
#demo2 {
text-align: center;
font-family: Helvetica;
background: IndianRed;
...