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Correct way to populate an Array with a Range in Ruby
...hrough a book which gives examples of Ranges being converted to equivalent arrays using their "to_a" methods
6 Answers
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What are the advantages of NumPy over regular Python lists?
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NumPy's arrays are more compact than Python lists -- a list of lists as you describe, in Python, would take at least 20 MB or so, while a NumPy 3D array with single-precision floats in the cells would fit in 4 MB. Access in reading a...
Python's equivalent of && (logical-and) in an if-statement
...ou create a sequence container.
See also 4.1. Truth Value Testing.
NumPy arrays and subclasses
Probably a bit beyond the scope of the original question but in case you're dealing with NumPy arrays or subclasses (like Pandas Series or DataFrames) then the implicit bool call
will raise the dreaded ...
Query for array elements inside JSON type
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json in Postgres 9.3+
Unnest the JSON array with the function json_array_elements() in a lateral join in the FROM clause and test for its elements:
WITH reports(data) AS (
VALUES ('{"objects":[{"src":"foo.png"}, {"src":"bar.png"}]
, "background":"ba...
PHP equivalent of .NET/Java's toString()
...nverted to string. Is there a general solutions that can convert anything (arrays+objects+whatever) to a string?
– ripper234
Jan 3 '13 at 15:42
3
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PHP parse/syntax errors; and how to solve them
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Unexpected [
These days, the unexpected [ array bracket is commonly seen on outdated PHP versions. The short array syntax is available since PHP >= 5.4. Older installations only support array().
$php53 = array(1, 2, 3);
$php54 = [1, 2, 3];
⇑
Array fu...
How do I store an array in localStorage? [duplicate]
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@Howdy_McGee As localStorage only supports strings, arrays must be converted to a string format. The best way to do this is to convert it into a JSON array as it is easy to convert between the two states (JSON is just a long piece of string data). You may want to read up on JS...
Quicksort vs heapsort
...han worst case in Quicksort. Heapsort doesn't need more memory for another array to putting ordered data as is needed by Mergesort. So why do comercial applications stick with Quicksort? What Quicksort has that is so special over others implementations?
I've tested the algorithms myself and I've se...
Can I pass an array as arguments to a method with variable arguments in Java?
... variable arity parameter will be evaluated and the results stored into an array that will be passed to the method invocation.
Here's an example to illustrate:
public static String ezFormat(Object... args) {
String format = new String(new char[args.length])
.replace("\0", "[ %s ]");
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How to remove the querystring and get only the url?
...explode() is less direct because it must produce a potentially two-element array by which the first element must be accessed.
Some other techniques may break when the querystring is missing or potentially mutate other/unintended substrings in the url -- these techniques should be avoided.
A demons...