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How to determine if Javascript array contains an object with an attribute that equals a given value?
I have an array like
24 Answers
24
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How to convert image to byte array
Can anybody suggest how I can convert an image to a byte array and vice versa?
12 Answers
...
MongoDB Aggregation: How to get total records count?
... felt when I finally achieved it LOL.
$result = $collection->aggregate(array(
array('$match' => $document),
array('$group' => array('_id' => '$book_id', 'date' => array('$max' => '$book_viewed'), 'views' => array('$sum' => 1))),
array('$sort' => $sort),
// get tot...
How do you get a string to a character array in JavaScript?
How do you convert a string to a character array in JavaScript?
13 Answers
13
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Why does ++[[]][+[]]+[+[]] return the string “10”?
...t the first element from [[]], it is true that:
[[]][0] returns the inner array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by one and return the incremented result”. So ++[[]][0]...
get dictionary value by key
...
It's as simple as this:
String xmlfile = Data_Array["XML_File"];
Note that if the dictionary doesn't have a key that equals "XML_File", that code will throw an exception. If you want to check first, you can use TryGetValue like this:
string xmlfile;
if (!Data_Array.Tr...
Difference between map and collect in Ruby?
... actually any difference between doing a map and doing a collect on an array in Ruby/Rails?
5 Answers
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What's the difference between echo, print, and print_r in PHP?
...f a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable form: strings are not quoted, type information is omitted, array sizes aren't given, etc.
var_dump is usually more useful than print_r when debugging, i...
Create an empty object in JavaScript with {} or new Object()?
... '/img/picture.jpg',
width: 300,
height: 200
};
Arrays
For arrays, there's similarly almost no benefit to ever using new Array(); over []; - with one minor exception:
var emptyArray = new Array(100);
creates a 100 item long array with all slots containing undefined - w...
Why does the order of the loops affect performance when iterating over a 2D array?
...
As others have said, the issue is the store to the memory location in the array: x[i][j]. Here's a bit of insight why:
You have a 2-dimensional array, but memory in the computer is inherently 1-dimensional. So while you imagine your array like this:
0,0 | 0,1 | 0,2 | 0,3
----+-----+-----+----
1,0...