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Circular (or cyclic) imports in Python
...retty thoroughly.
Imports are pretty straightforward really. Just remember the following:
'import' and 'from xxx import yyy' are executable statements. They execute
when the running program reaches that line.
If a module is not in sys.modules, then an import creates the new module
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JavaScript pattern for multiple constructors
...loading, including for methods or constructors.
If you want a function to behave differently depending on the number and types of parameters you pass to it, you'll have to sniff them manually. JavaScript will happily call a function with more or fewer than the declared number of arguments.
functio...
Assign multiple columns using := in data.table, by group
What is the best way to assign to multiple columns using data.table ? For example:
2 Answers
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Javascript - sort array based on another array
Is it possible to sort and rearrange an array that looks like this:
21 Answers
21
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How can I count the occurrences of a list item?
...oop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the other answers.
share
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Items in JSON object are out of order using “json.dumps”?
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Both Python dict (before Python 3.7) and JSON object are unordered collections. You could pass sort_keys parameter, to sort the keys:
>>> import json
>>> json.dumps({'a': 1, 'b': 2})
'{"b": 2, "a": 1}'
>...
Defining a variable with or without export
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export makes the variable available to sub-processes.
That is,
export name=value
means that the variable name is available to any process you run from that shell process. If you want a process to make use of this variable, use export, and run ...
Python multiprocessing pool.map for multiple arguments
In the Python multiprocessing library, is there a variant of pool.map which supports multiple arguments?
19 Answers
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R - Concatenate two dataframes?
Given two dataframes a and b :
5 Answers
5
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Test whether a Ruby class is a subclass of another class
I would like to test whether a class inherits from another class, but there doesn't seem to exist a method for that.
2 Answ...