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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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Adding external library into Qt Creator project
... this is like this:
LIBS += -L/path/to -lpsapi
This way it will work on all platforms supported by Qt. The idea is that you have to separate the directory from the library name (without the extension and without any 'lib' prefix). Of course, if you are including a Windows specific lib, this reall...
Windbg Step 2 分析程序堆栈实战 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...http: www.cnblogs.com killmyday#include"stdafx.h"#include<tchar.h>#ifdef_UNICODE#define_ttol_wtol#else#define_ttolatol#e...转载+整理 http://www.cnblogs.com/killmyday
#include "stdafx.h"
#include <tchar.h>
#ifdef _UNICODE
#define _ttol _wtol
#else
#define _ttol atol
#endif
voi...
How to initialize private static members in C++?
...t be done outside of any function.
Note: Matt Curtis: points out that C++ allows the simplification of the above if the static member variable is of const int type (e.g. int, bool, char). You can then declare and initialize the member variable directly inside the class declaration in the header fil...
What breaking changes are introduced in C++11?
...nity, whereas C++0x always rounds the result toward 0.
(admittedly not really a compatibility problem for most people).
Valid C++ 2003 code that uses the keyword auto as a storage class specifier may be invalid in C++0x.
Narrowing conversions cause incompatibilities with C++03. For ex...
How do I terminate a thread in C++11?
...
You could call std::terminate() from any thread and the thread you're referring to will forcefully end.
You could arrange for ~thread() to be executed on the object of the target thread, without a intervening join() nor detach() on that...
Regex not operator
...: lookahead) this doesn't (hence: negative) match this. But it doesn't actually consume the characters it matches (hence: zero-width).
There are actually 4 combinations of lookarounds with 2 axes:
lookbehind / lookahead : specifies if the characters before or after the point are considered
positi...
Replace all non-alphanumeric characters in a string
...
If you handle unicode a lot, you may also need to keep all non-ASCII unicode symbols: re.sub("[\x00-\x2F\x3A-\x40\x5B-\x60\x7B-\x7F]+", " ", ":%# unicode ΣΘΙП@./\n")
– zhazha
Jul 13 '16 at 7:43
...
Is there a NumPy function to return the first index of something in an array?
...:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so woul...
PDO Prepared Inserts multiple rows in single query
... table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, the code:
function placeholders($text, $count=0, $separator=","){
$result = array();
if($count > 0){
for($x=0; $x<$count; $x++){
$re...