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Sort Dictionary by keys
...[
"A" : [1, 2],
"Z" : [3, 4],
"D" : [5, 6]
]
let sortedKeys = Array(dictionary.keys).sorted(<) // ["A", "D", "Z"]
EDIT:
The sorted array from the above code contains keys only, while values have to be retrieved from the original dictionary. However, 'Dictionary' is also a 'Collect...
How to find the array index with a value?
...List.indexOf(200); // 1
You will get -1 if it cannot find a value in the array.
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Set operations (union, intersection) on Swift array?
...y standard library calls I can use to either perform set operations on two arrays, or implement such logic myself (ideally as functionally and also efficiently as possible)?
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Python memory usage of numpy arrays
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Given an array of numbers, return array of products of all other numbers (no division)
...explanation of polygenelubricants method is:
The trick is to construct the arrays (in the case for 4 elements)
{ 1, a[0], a[0]*a[1], a[0]*a[1]*a[2], }
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Both of which can be done in O(n) by starting at t...
How does python numpy.where() work?
...short answer is that they don't.
Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolean arrays where the given condition is true).
E.g.
x = np.arange(9).reshape(3,3)
print x > 5
yields:
array([[False, False, False],
[Fals...
Is std::vector so much slower than plain arrays?
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How does the Java 'for each' loop work?
...erable interface.
Also, if the right-hand side of the for (:) idiom is an array rather than an Iterable object, the internal code uses an int index counter and checks against array.length instead. See the Java Language Specification.
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How do I read CSV data into a record array in NumPy?
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...