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PHP append one array to another (not array_push or +)
...', 'b');
$b = array('c', 'd');
$merge = array_merge($a, $b);
// $merge is now equals to array('a','b','c','d');
Doing something like:
$merge = $a + $b;
// $merge now equals array('a','b')
Will not work, because the + operator does not actually merge them. If they $a has the same keys as $b, it...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...llow copy:
d = copy.copy(c)
print id(c) == id(d) # False - d is now a new object
print id(c[0]) == id(d[0]) # True - d[0] is the same object as c[0]
Using a deep copy:
d = copy.deepcopy(c)
print id(c) == id(d) # False - d is now a new object
print id(c[0]) == id(d[0]) #...
How to check if a number is a power of 2
...that
is, the result is true if and only if both its operands are true.
Now let's take a look at how this all plays out:
The function returns boolean (true / false) and accepts one incoming parameter of type unsigned long (x, in this case). Let us for the sake of simplicity assume that someone ...
Is std::vector so much slower than plain arrays?
...d::vector<Pixel> pixels(dimensions * dimensions, Pixel(255,0,0));
Now doing the same timing again:
g++ -O3 Time.cpp -I <MyBoost>
./a.out
UseVector completed in 2.216 seconds
The vector now performance only slightly worse than the array. IMO this difference is insignificant...
Can a class member function template be virtual?
... just indirection, and there is no "runtime figuring out" involved, it is known during compile time that the function to be called is the one pointed to by the n-th pointer in the vtable. "Figuring out" implies there are type checks and such, which is not the case. Once the run-time system figured o...
Gmail's new image caching is breaking image links in newsletter
.... GoogleImagesProxy has stored these statuses into its own proxy server.
Now tried to open your email, you noticed some 404 statuses against your images. This is something understandable. You immediately realized that you forgot to upload some images, so you uploaded them to your server. and also ...
Test if remote TCP port is open from a shell script
... > /dev/tcp/sfsfdfdff.com/80'
bash: sfsfdfdff.com: Name or service not known
bash: /dev/tcp/sfsfdfdff.com/80: Invalid argument
$ echo $?
1
# Connection not established by the timeout
$ timeout 1 bash -c 'cat < /dev/null > /dev/tcp/google.com/81'
$ echo $?
124
What's happening here is tha...
Basic example of using .ajax() with JSONP?
...lly a simply trick to overcome XMLHttpRequest same domain policy. (As you know one cannot send AJAX (XMLHttpRequest) request to a different domain.)
So - instead of using XMLHttpRequest we have to use script HTMLl tags, the ones you usually use to load JS files, in order for JS to get data from ano...
How to subtract X day from a Date object in Java?
...h Java 8's date time API change, Use LocalDate
LocalDate date = LocalDate.now().minusDays(300);
Similarly you can have
LocalDate date = someLocalDateInstance.minusDays(300);
Refer to https://stackoverflow.com/a/23885950/260990 for translation between java.util.Date <--> java.time.LocalDa...
How to convert floats to human-readable fractions?
...t;(double)0x7FFFFFFF) break; // AF: representation failure
}
/* now remaining x is between 0 and 1/ai */
/* approx as either 0 or 1/m where m is max that will fit in maxden */
/* first try zero */
printf("%ld/%ld, error = %e\n", m[0][0], m[1][0],
startx - ((double) ...