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How to convert int[] to Integer[] in Java?
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With Java 8, int[] can be converted to Integer[] easily:
int[] data = {1,2,3,4,5,6,7,8,9,10};
// To boxed array
Integer[] what = Arrays.stream( data ).boxed().toArray( Integer[]::new );
Integer[] ever = IntStream.of( data ).boxed().toArray( Integer[]::new );
// To boxed list
List<Integer> ...
What does curly brackets in the `var { … } = …` statements do?
...r with Python, it's similar to this syntax:
>>> a, (b, c) = (1, (2, 3))
>>> a, b, c
(1, 2, 3)
The first code chunk is shorthand for:
var {Hotkey: Hotkey} = require("sdk/hotkeys");
// Or
var Hotkey = require("sdk/hotkeys").Hotkey;
You can rewrite the second code chunk as:
let...
PHP ORMs: Doctrine vs. Propel
...ria):
<?php
// Propel
$c = new Criteria();
$c->add(ExamplePeer::ID, 20);
$items = ExamplePeer::doSelectJoinFoobar($c);
// Doctrine
$items = Doctrine_Query::create()
->from('Example e')
->leftJoin('e.Foobar')
->where('e.id = ?', 20)
->execute();
?>
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Should commit messages be written in present or past tense? [closed]
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12 Answers
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How to convert a negative number to positive?
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216
>>> n = -42
>>> -n # if you know n is negative
42
>>> abs(n) ...
Turning a Comma Separated string into individual rows
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270
You can use the wonderful recursive functions from SQL Server:
Sample table:
CREATE TABLE ...
Append value to empty vector in R?
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212
Appending to an object in a for loop causes the entire object to be copied on every iteration,...
How do I get an empty array of any size in python?
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241
If by "array" you actually mean a Python list, you can use
a = [0] * 10
or
a = [None] * 10...
Determine the number of NA values in a column
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321
You're over-thinking the problem:
sum(is.na(df$col))
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How to get a Docker container's IP address from the host
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52 Answers
52
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