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Change column type from string to float in Pandas
...ost) any other type (even if it's not necessarily sensible to do so). Also allows you to convert to categorial types (very useful).
infer_objects() - a utility method to convert object columns holding Python objects to a pandas type if possible.
convert_dtypes() - convert DataFrame columns to the ...
static const vs #define
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Personally, I loathe the preprocessor, so I'd always go with const.
The main advantage to a #define is that it requires no memory to store in your program, as it is really just replacing some text with a literal value. It also has...
Comparing mongoose _id and strings
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The accepted answers really limit what you can do with your code. For example, you would not be able to search an array of Object Ids by using the equals method. Instead, it would make more sense to always cast to string and compare the keys.
Her...
or (HTML5)
...ipt interaction when clicking on a menu item.
nav: the navigation for the site.
menu: the menu for a web application.
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Private and Protected Members : C++
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Public members of a class A are accessible for all and everyone.
Protected members of a class A are not accessible outside of A's code, but is accessible from the code of any class derived from A.
Private members of a class A are not accessible outside of A's code, or f...
What is the Java equivalent of PHP var_dump?
...for free. It is done with convention rather than language constructs. In all data transfer classes (and maybe even in all classes you write...), you should implement a sensible toString method. So here you need to override toString() in your Person class and return the desired state.
There are u...
C++ equivalent of java's instanceof
...nceof) you'd better ask yourself whether it's a necessary thing. It's generally a sign of poor design.
Typical workarounds is putting the special behaviour for the class you are checking for into a virtual function on the base class or perhaps introducing something like a visitor where you can int...
What does a colon following a C++ constructor name do? [duplicate]
...ctor's signature is:
MyClass();
This means that the constructor can be called with no parameters. This makes it a default constructor, i.e., one which will be called by default when you write MyClass someObject;.
The part : m_classID(-1), m_userdata(0) is called initialization list. It is a way...
Unix - create path of folders and file
...her/path/here && touch $_/cpredthing.txt. The $_ expands to essentially the "last argument in the last command executed".
– Sgnl
Apr 19 '16 at 1:37
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What is the use of static constructors?
...required configuration data into readonly fields, etc.
It is run automatically by the runtime the first time it is needed (the exact rules there are complicated (see "beforefieldinit"), and changed subtly between CLR2 and CLR4). Unless you abuse reflection, it is guaranteed to run at most once (eve...