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Why use Abstract Base Classes in Python?
...emented classes.
Long version
There is a contract between a class and its callers. The class promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a s...
How to increase font size in a plot in R?
...need to use cex.names (if you're a human who reads things from an upright position, you might also want las=2)
– geneorama
Jan 12 '16 at 20:13
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Should __init__() call the parent class's __init__()?
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In Python, calling the super-class' __init__ is optional. If you call it, it is then also optional whether to use the super identifier, or whether to explicitly name the super class:
object.__init__(self)
In case of object, calling th...
SASS - use variables across multiple files
I would like to keep one central .scss file that stores all SASS variable definitions for a project.
6 Answers
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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
Forward host port to docker container
...e to run a process in a Docker container to listen to the queue and (optionally) write to the database.
5 Answers
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C# vs C - Big performance difference
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Since you never use 'root', the compiler may have been removing the call to optimize your method.
You could try to accumulate the square root values into an accumulator, print it out at the end of the method, and see what's going on.
Edit : see Jalf's answer below
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
How to install Boost on Ubuntu
I'm on Ubuntu, and I want to install Boost. I tried with
7 Answers
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