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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
I have a data frame df and I use several columns from it to groupby :
7 Answers
7
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Seeing escape characters when pressing the arrow keys in python shell
...o move around in the current line or get previous commands (with arrow-up) etc.
23 Answers
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Getting root permissions on a file inside of vi? [closed]
...eed to add your user to sudoer file first, enter the root user, and open /etc/sudoers file, add your_username ALL=(ALL) ALL under the line root ALL=(ALL) ALL, quit and save.
– coolesting
Oct 25 '11 at 3:18
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Is there any good dynamic SQL builder library in Java? [closed]
... a simpler API and supports also other backends (JPA, JDO, Lucene, Mongodb etc.); I am also in the company behind Querydsl
– Timo Westkämper
Apr 12 '11 at 5:55
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Can someone explain this 'double negative' trick? [duplicate]
...single operand can be converted to true; otherwise, returns true.
So if getContext gives you a "falsey" value, the !! will make it return the boolean value false. Otherwise it will return true.
The "falsey" values are:
false
NaN
undefined
null
"" (empty string)
0
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MySQL high CPU usage [closed]
...ication is running, if there's duplicate queries, how long they're taking, etc, etc. An example of something like this is one I've been working on called PHP Profiler but there are many out there. If you're using a piece of software like Drupal, Joomla or Wordpress you'll want to ask around within t...
How to secure MongoDB with username and password
...at starts with #auth=true in your mongod configuration file (default path /etc/mongo.conf). This will enable authentication for mongodb.
Then, restart mongodb : sudo service mongod restart
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C/C++ include header file order
...ers from other non-standard, non-system libraries (for example, Qt, Eigen, etc).
Headers from other "almost-standard" libraries (for example, Boost)
Standard C++ headers (for example, iostream, functional, etc.)
Standard C headers (for example, cstdint, dirent.h, etc.)
If any of the headers have a...
General guidelines to avoid memory leaks in C++ [closed]
...ption safety and resource disposal in C++, and no other pattern (sandwich, etc.) will give you both (and most of the time, it will give you none).
See below a comparison of RAII and non RAII code:
void doSandwich()
{
T * p = new T() ;
// do something with p
delete p ; // leak if the p pro...
How to get UTF-8 working in Java webapps?
... in my Java webapp (servlets + JSP, no framework used) to support äöå etc. for regular Finnish text and Cyrillic alphabets like ЦжФ for special cases.
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