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Converting file size in bytes to human-readable string
I'm using this function to convert a file size in bytes to a human-readable file size:
19 Answers
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Modifying a subset of rows in a pandas dataframe
Assume I have a pandas DataFrame with two columns, A and B. I'd like to modify this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
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What issues should be considered when overriding equals and hashCode in Java?
What issues / pitfalls must be considered when overriding equals and hashCode ?
11 Answers
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Why have header files and .cpp files? [closed]
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Well, the main reason would be for separating the interface from the implementation. The header declares "what" a class (or whatever is being implemented) will do, while the cpp file defines "how" it will perform those features.
This reduces dependenc...
How do you sort an array on multiple columns?
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If owner names differ, sort by them. Otherwise, use publication name for tiebreaker.
function mysortfunction(a, b) {
var o1 = a[3].toLowerCase();
var o2 = b[3].toLowerCase();
var p1 = a[1].toLowerCase();
var p2 = b[1].toLowerCase();
if (o1...
Cartesian product of multiple arrays in JavaScript
...nilla JS
Original 2017 Answer: 2-line answer with vanilla JS:
(see updates below)
All of the answers here are overly complicated, most of them take 20 lines of code or even more.
This example uses just two lines of vanilla JavaScript, no lodash, underscore or other libraries:
let f = (a, b) => []...
Copy a variable's value into another
I have a variable which has a JSON object as its value. I directly assign this variable to some other variable so that they share the same value. This is how it works:
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How do I modify fields inside the new PostgreSQL JSON datatype?
With postgresql 9.3 I can SELECT specific fields of a JSON data type, but how do you modify them using UPDATE? I can't find any examples of this in the postgresql documentation, or anywhere online. I have tried the obvious:
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Zip lists in Python
...y elements. Each element is a three-tuple.
See for yourself:
In [1]: a = b = c = range(20)
In [2]: zip(a, b, c)
Out[2]:
[(0, 0, 0),
(1, 1, 1),
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(17, 17, 17),
(18, 18, 18),
(19, 19, 19)]
To find out how many elements each tuple contains, you could examine the length of the first element...
Graph Algorithm To Find All Connections Between Two Arbitrary Vertices
I am trying to determine the best time efficient algorithm to accomplish the task described below.
16 Answers
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