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Append column to pandas dataframe
... way probably only matters when you consider edge cases. For instance here if both DataFrames had a 'data' column the join would fail, whereas a concat would give you two columns named 'data'.
– U2EF1
Dec 16 '13 at 20:37
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What is an abstract class in PHP?
...nd non-abstract methods, but it must contain at least one abstract method. If a class has at least one abstract method, then the class must be declared abstract.
Note: Traits support the use of abstract methods in order to impose requirements upon the exhibiting class.
Example below :
class ...
Setting Vim whitespace preferences by filetype
...ndent based on the size of tabstop, and then spaces after that. Of course, if expandtab is on, all the tabs that get inserted are converted to spaces. stackoverflow.com/questions/1562336/… might help further. Without expand tab, Peter's answer would insert tabs that are 2 chars wide, not spaces.
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Rotating a two-dimensional array in Python
...tual list. So:
rotated = list(reversed(list(zip(*original))))
We can simplify that a bit by using the "Martian smiley" slice rather than reversed()... then we don't need the outer list():
rotated = list(zip(*original))[::-1]
Of course, you could also simply rotate the list clockwise three times. :...
When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?
...se. That is without the examples, I was still unsure, but with them, I am now sure about what the other answers mean.
– Solx
Apr 29 '14 at 14:41
1
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How to convert std::string to lower case?
...no way to know whether the character is lowercase or uppercase otherwise.
If you really hate tolower(), here's a specialized ASCII-only alternative that I don't recommend you use:
char asciitolower(char in) {
if (in <= 'Z' && in >= 'A')
return in - ('Z' - 'z');
return...
Is there a difference between single and double quotes in Java?
Is there a difference between single and double quotes in Java?
4 Answers
4
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Android custom dropdown/popup menu
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Now it can also be used in lower versions ie below 3.0(honeycomb) by using the v7 compat support library..
– AndroidMech
Jun 6 '14 at 13:27
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pandas resample documentation
...and a section about resampling.
Note that there isn't a list of all the different how options, because it can be any NumPy array function and any function that is available via groupby dispatching can be passed to how by name.
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Rails 4: before_filter vs. before_action
...action not before_filter . It seems to do the same thing. So what's the difference between these two?
5 Answers
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