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What is the difference between join and merge in Pandas?
...r
key
foo 1 4
bar 2 5
The same functionality can be had by using merge on the columns follows:
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]})
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]})
left.merge(right, on=('key'), suffixes=('_l', '_r...
Referring to the null object in Python
...eton None.
The best way to check things for "Noneness" is to use the identity operator, is:
if foo is None:
...
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Find which version of package is installed with pip
Using pip, is it possible to figure out which version of a package is currently installed?
15 Answers
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Convert json data to a html table [closed]
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edited Jan 3 '17 at 8:27
Peter B
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How to use the TextWatcher class in Android?
Can anyone tell me how to mask the substring in EditText or how to change EditText substring input to password type or replace by another character like this 123xxxxxxxxx3455
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What optimizations can GHC be expected to perform reliably?
GHC has a lot of optimizations that it can perform, but I don't know what they all are, nor how likely they are to be performed and under what circumstances.
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Mongoose, Select a specific field with find
I'm trying to select only a specific field with
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When should I use nil and NULL in Objective-C?
.... The main difference is that you can send messages to nil, so you can use it in some places where null cant work.
In general, just use nil.
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Python: access class property from string [duplicate]
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edited Oct 1 '17 at 15:04
serv-inc
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putting current class as return type annotation [duplicate]
...issue has been resolved by not evaluating the annotations at function definition time. Instead, they are preserved in __annotations__ in string form. This is called Postponed Evaluation of Annotations, introduced in PEP 563.
Also note:
Deprecation policy
Starting with Python 3.7, a __futu...