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Create an array with same element repeated multiple times
...return a;
}
It doubles the array in each iteration, so it can create a really large array with few iterations.
Note: You can also improve your function a lot by using push instead of concat, as concat will create a new array each iteration. Like this (shown just as an example of how you can wor...
How to install MySQLdb (Python data access library to MySQL) on Mac OS X?
...
Update for those using Python3:
You can simply use conda install mysqlclient to install the libraries required to use MySQLdb as it currently exists. The following SO question was a helpful clue: Python 3 ImportError: No module named 'ConfigParser' . Installing mysqlclient will install...
Calculate distance between 2 GPS coordinates
...y solution:
#include <math.h>
#include "haversine.h"
#define d2r (M_PI / 180.0)
//calculate haversine distance for linear distance
double haversine_km(double lat1, double long1, double lat2, double long2)
{
double dlong = (long2 - long1) * d2r;
double dlat = (lat2 - lat1) * d2r;
...
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
...l reasons: it is
inherently O(n) in the length of the
strings; it typically requires reads
from several regions of memory, which
take time; and the reads fills up the
processor cache, meaning there is less
cache available for other needs. With
interned strings, a simple object
identi...
How to determine height of UICollectionView with FlowLayout
...y question: I was completely searching in the wrong place, digging through all the documentation I could find on UICollectionView.
The simple and easy solution lies in the underlying layout: Just call collectionViewContentSize on your myCollectionView.collectionViewLayout property and you get the h...
How to post data in PHP using file_get_contents?
...Sending an HTTP POST request using file_get_contents is not that hard, actually : as you guessed, you have to use the $context parameter.
There's an example given in the PHP manual, at this page : HTTP context options (quoting) :
$postdata = http_build_query(
array(
'var1' => 'some...
Java “lambda expressions not supported at this language level”
...: android { compileOptions { sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } }
– BaDo
Sep 25 '15 at 2:30
...
Cost of len() function
...
Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
What is the easiest way in C# to trim a newline off of a string?
...impression \n was not a white space but it is and .TrimEnd and .Trim clear all white space characters natively
– David Carrigan
May 13 '15 at 20:46
...
mongodb count num of distinct values per field/key
...}
},
{ $unwind: "$keywords" },
{
$group: {
_id: {$toLower: '$keywords'},
count: { $sum: 1 }
}
},
{
$match: {
count: { $gte: 2 }
}
},
{ $sort : { count : -1} },
{ $limit : 100 }
]);
that give result ...