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Python pandas Filtering out nan from a data selection of a column of strings
...
Just drop them:
nms.dropna(thresh=2)
this will drop all rows where there are at least two non-NaN.
Then you could then drop where name is NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob N...
Best exception for an invalid generic type argument
...ere's a way in which NotSupportedException is obviously good enough, especially given its common-sense meaning. Having said that, I'm not sure if it's just right.
Given the purpose of Unconstrained Melody ...
There are various useful things that can be done with generic
methods/classes where ...
Analyze audio using Fast Fourier Transform
...efficients you get out will be imaginary numbers even though your input is all real values. In order to get the amount of power in each frequency, you need to calculate the magnitude of the FFT coefficient for each frequency. This is not just the real component of the coefficient, you need to calcul...
How can I get a view's current width and height when using autolayout constraints?
...our existing constraints, the answer is not to inspect the constraints manually, since that would require you to re-implement the entire constraint-solving logic of the auto layout system in order to interpret those constraints. Instead, what you should do is just ask auto layout to update that layo...
How do I deal with certificates using cURL while trying to access an HTTPS url?
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This error is related to a missing package: ca-certificates. Install it.
In Ubuntu Linux (and similar distro):
# apt-get install ca-certificates
In CygWin via Apt-Cyg
# apt-cyg install ca-certificates
In Arch Linux (Raspberry Pi)
# pacman -S ca-certificates
The documentation te...
Java Enum Methods - return opposite direction enum
... method that returns the opposite direction (the following is not syntactically correct, i.e, enums cannot be instantiated, but it illustrates my point). Is this possible in Java?
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What are the Differences Between “php artisan dump-autoload” and “composer dump-autoload”?
...it different:
1) It will in fact use Composer for some stuff
2) It will call Composer with the optimize flag
3) It will 'recompile' loads of files creating the huge bootstrap/compiled.php
4) And also will find all of your Workbench packages and composer dump-autoload them, one by one.
...
Polymorphism: Why use “List list = new ArrayList” instead of “ArrayList list = new ArrayList”? [dupl
... code only knows that data is of type List, which is preferable because it allows you to switch between different implementations of the List interface with ease.
For instance, say you were writing a fairly large 3rd party library, and say that you decided to implement the core of your library with...
How to dynamically create CSS class in JavaScript and apply?
I need to create a CSS stylesheet class dynamically in JavaScript and assign it to some HTML elements like - div, table, span, tr, etc and to some controls like asp:Textbox, Dropdownlist and datalist.
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What is the difference between “instantiated” and “initialized”?
... it to be. The value is what you assign to it.
Variables are Initialized
All variables are always given an initial value at the point the variable is declared. Thus all variables are initialized.
For value types, like int the compiler will give them a valid value if you do not do so explicitly. i...