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Pandas count(distinct) equivalent
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@user32185 you'd have to drop it into an apply call with a lambda. For instance, df.groupby('YEARMONTH')['CLIENTCODE'].apply(lambda x: x.unique().shape[0]).
– 3novak
Apr 17 '18 at 18:59
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Declaring an enum within a class
...t other classes use then you might as well make it global (or at least outside Car).
It makes no difference. If there is a global one then the local one is still used anyway as it is closer to the current scope. Note that if you define those function outside of the class definition then you'll need ...
How to git-svn clone the last n revisions from a Subversion repository?
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SVN uses consecutive integers to identify revisions, making it even more trivial to walk back n commits ...
– harmic
Apr 20 '17 at 1:15
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Array include any value from another array?
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(cheeses & foods).empty?
As Marc-André Lafortune said in comments, & works in linear time while any? + include? will be quadratic. For larger sets of data, linear time will be faster. For small data sets, any? + include? may be faster as shown by Lee Jarvis' answer -- pro...
How to pip install a package with min and max version range?
... var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
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How to make the tab character 4 spaces instead of 8 spaces in nano?
...use nano with a language like python (as in your example) it's also a good idea to convert tabs to spaces.
Edit your ~/.nanorc file (or create it) and add:
set tabsize 4
set tabstospaces
If you already got a file with tabs and want to convert them to spaces i recommend the expandcommand (shell):...
Difference between Array and List in scala
...hich fast random access is important.
Mutable Structures
ListBuffer provides a constant-time conversion to a List which is reason alone to use ListBuffer if such later conversion is required.
A scala Array should be implemented on the JVM by a Java array, and hence an Array[Int] may be much more...
Creating stored procedure and SQLite?
...client/server (NOT SQLite!), For these, performance is a key issue when deciding where to put your business logic. Executing business logic be it query OR interative OR conditional code inside an SP in the SQL engine can (1) improve data retrieval performance, (2) reduce network traffic (3) reduce ...
What is the difference between lock and Mutex?
...h for the common case.
The Monitor (and the lock keyword) are, as Darin said, restricted to the AppDomain. Primarily because a reference to a memory address (in the form of an instantiated object) is required to manage the "lock" and maintain the identity of the Monitor
The Mutex, on the other ha...
bool to int conversion
...the value is 1, 4>5 would evaluate to 0.
EDIT: Jens in the comment said, C99 has _Bool type. bool is a macro defined in stdbool.h header file. true and false are also macro defined in stdbool.h.
§7.16 from C99 says,
The macro bool expands to _Bool.
[..] true which expands to the int...