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Generate random numbers using C++11 random library
...lude <random>
#include <iostream>
int main() {
std::random_device rd;
std::mt19937 mt(rd());
std::uniform_real_distribution<double> dist(1.0, 10.0);
for (int i=0; i<16; ++i)
std::cout << dist(mt) << "\n";
}
We use random_device once to see...
Hadoop “Unable to load native-hadoop library for your platform” warning
...entOS. The reason you saw that warning is the native Hadoop library $HADOOP_HOME/lib/native/libhadoop.so.1.0.0 was actually compiled on 32 bit.
Anyway, it's just a warning, and won't impact Hadoop's functionalities.
Here is the way if you do want to eliminate this warning, download the source cod...
PHP mail function doesn't complete sending of e-mail
...les (or in a master configuration file) will enable error reporting.
error_reporting(-1);
ini_set('display_errors', 'On');
set_error_handler("var_dump");
See How can I get useful error messages in PHP? — this answer for more details on this.
Make sure the mail() function is called
It may seem...
Geometric Mean: is there a built-in?
...gth(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log(x[x > 0]), na.rm=na.rm) / length(x))
}
Thanks to @ben-bolker for noting the na.rm pass-through and @Gregor for making sure it works correctly.
I think some of the comments ...
How to iterate through all git branches using bash script
...rmat='%(refname:short)'
iterate through all git branches: mapfile -t -C my_callback -c 1 < <( get_branches )
example:
my_callback () {
INDEX=${1}
BRANCH=${2}
echo "${INDEX} ${BRANCH}"
}
get_branches () {
git branch --all --format='%(refname:short)'
}
# mapfile -t -C my_callback -c 1...
Mongodb Explain for Aggregation framework
...erations
explain:true
db.collection.aggregate([
{ $project : { "Tags._id" : 1 }},
{ $unwind : "$Tags" },
{ $match: {$or: [{"Tags._id":"tag1"},{"Tags._id":"tag2"}]}},
{ $group: {
_id : "$_id",
count: { $sum:1 }
}},
{$sort: {"count":-1}}
],
{
explain...
Unique Constraint in Entity Framework Code First
...
CreateIndex("TableName", new string[2] { "Column1", "Column2" }, true, "IX_UniqueColumn1AndColumn2");
Something like that:
namespace Sample.Migrations
{
using System;
using System.Data.Entity.Migrations;
public partial class TableName_SetUniqueCompositeIndex : DbMigration
{
...
Detect Android phone via Javascript / jQuery
...w.location = 'http://android.davidwalsh.name';
}
PHP:
$ua = strtolower($_SERVER['HTTP_USER_AGENT']);
if(stripos($ua,'android') !== false) { // && stripos($ua,'mobile') !== false) {
header('Location: http://android.davidwalsh.name');
exit();
}
Edit : As pointed out in some comments...
How can I delete all Git branches which have been merged?
...ip, you can add it to the egrep command like the following. The branch skip_branch_name will not be deleted.
git branch --merged| egrep -v "(^\*|master|dev|skip_branch_name)"
To delete all local branches that are already merged into the currently checked out branch:
git branch --merged | egrep -v "...
CGContextDrawImage draws image upside down when passed UIImage.CGImage
...ingPrintingiOS/GraphicsDrawingOverview/GraphicsDrawingOverview.html#//apple_ref/doc/uid/TP40010156-CH14-SW4
Flipping the Default Coordinate System
Flipping in UIKit drawing modifies the backing CALayer to align a drawing environment having a LLO coordinate system with the default coordinate...