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How to calculate the difference between two dates using PHP?
...rom this it's rather easy to calculate different time periods.
$date1 = "2007-03-24";
$date2 = "2009-06-26";
$diff = abs(strtotime($date2) - strtotime($date1));
$years = floor($diff / (365*60*60*24));
$months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
$days = floor(($diff - $years ...
Generate random numbers using C++11 random library
...u can see his full talk here: http://channel9.msdn.com/Events/GoingNative/2013/rand-Considered-Harmful
#include <random>
#include <iostream>
int main() {
std::random_device rd;
std::mt19937 mt(rd());
std::uniform_real_distribution<double> dist(1.0, 10.0);
for (in...
Returning first x items from array
...ray_slice returns a slice of an array
$sliced_array = array_slice($array, 0, 5)
is the code you want in your case to return the first five elements
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What's the fastest way to convert String to Number in JavaScript?
...
There are 4 ways to do it as far as I know.
Number(x);
parseInt(x, 10);
parseFloat(x);
+x;
By this quick test I made, it actually depends on browsers.
http://jsperf.com/best-of-string-to-number-conversion/2
Implicit marked the fastest on 3 browsers, but it makes the code hard to read… S...
Why is the shovel operator (
...
Proof:
a = 'foo'
a.object_id #=> 2154889340
a << 'bar'
a.object_id #=> 2154889340
a += 'quux'
a.object_id #=> 2154742560
So << alters the original string rather than creating a new one. The reason for this is that in ruby a += b is syntactic short...
Using [UIColor colorWithRed:green:blue:alpha:] doesn't work with UITableView seperatorColor?
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You need to divide by 255.0
Because I hardly ever use values between 1.0 and 0.0, I created a very simple UIColor category that does the messy looking division by itself: (from http://github.com/Jon889/JPGeneral)
//.h file
@interface UIColor (JPExtr...
Python: print a generator expression?
...ator expression is a "naked" for expression. Like so:
x*x for x in range(10)
Now, you can't stick that on a line by itself, you'll get a syntax error. But you can put parenthesis around it.
>>> (x*x for x in range(10))
<generator object <genexpr> at 0xb7485464>
This is som...
Is there a NumPy function to return the first index of something in an array?
...mensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so would
array[itemindex[0][1]][itemindex[1][1]]
numpy.where
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How do I get the full path to a Perl script that is executing?
...during execution. I discovered that depending on how you call the script $0 varies and sometimes contains the fullpath+filename and sometimes just filename . Because the working directory can vary as well I can't think of a way to reliably get the fullpath+filename of the script.
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Transposing a 2D-array in JavaScript
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210
array[0].map((_, colIndex) => array.map(row => row[colIndex]));
map calls a provided ...