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Replace None with NaN in pandas dataframe
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If you imported data from an SQL database, you can combine this with the answer below. This converts None (which isn't a string) to NaN. Then you can df['column'].replace(nan, "", inplace=True) if say you wanted None to be empty string.
– V...
Why do we use __init__ in Python classes?
...nd inherit some abstract characteristics and behavior from the human type (base-class) : that's inheritance. So all Humans can laugh and drink, therefore all child-classes can also! Inheritance (2).
But because they are all of the same kind (Type/base-class : Humans) you can exchange them sometimes...
What is “overhead”?
...ally referred to as "overhead" but rather is called "footprint." Also the base memory your program consumes (without regard to any data set that it's processing) is called its "footprint" as well.
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How is a tag different from a branch in Git? Which should I use, here?
... that may run concurrently with other development efforts on the same code base. Changes to a branch may eventually be merged back into another branch to unify them.
Usually you'll tag a particular version so that you can recreate it, e.g., this is the version we shipped to XYZ Corp. A branch is...
What's the difference between assignment operator and copy constructor?
...arguments and then assignment operator is used and new values are assigned based on RHS. In case copy constructor is used, still same constructor will be called, but values used for initialization is from other object.
– Rajesh
Mar 17 '18 at 3:40
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How to link godaddy domain with AWS Elastic Beanstalk environment?
...This solution is not effective from the point of SEO. See below my answer, based on Amazon's documentation.
– Vsevolod Krasnov
Aug 23 '16 at 9:00
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How do I move to end of line in Vim?
...re-pending the up and down commands with g make vim move the cursor screen-based, rather than line-based. I.e. gj and gk allow you to move up and down on a long line. Really useful.
– Druckles
Apr 11 '12 at 17:29
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Finding the type of an object in C++
... a bad_cast exception.
Make sure there is at least one virtual function in Base class to make dynamic_cast work.
Wikipedia topic Run-time type information
RTTI is available only for classes that are polymorphic, which means
they have at least one virtual method. In practice, this is not a
limitatio...
How can I get nth element from a list?
... list), lists may in fact not be the proper data structure. For O(1) index-based access there are more efficient alternatives, such as arrays or vectors.
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