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Sorting object property by values
If I have a JavaScript object such as:
38 Answers
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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...
Find the max of two or more columns with pandas
I have a dataframe with columns A , B . I need to create a column C such that for every record / row:
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
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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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Templated check for the existence of a class member function?
Is it possible to write a template that changes behavior depending on if a certain member function is defined on a class?
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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}'
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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 ...
How to find common elements from multiple vectors?
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There might be a cleverer way to go about this, but
intersect(intersect(a,b),c)
will do the job.
EDIT: More cleverly, and more conveniently if you have a lot of arguments:
Reduce(intersect, list(a,b,c))
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