大约有 40,000 项符合查询结果（耗时：0.0540秒） [XML]
What is the difference between quiet NaN and signaling NaN?
...+ in this answer instead of C because it offers the convenient std::numeric_limits::quiet_NaN and std::numeric_limits::signaling_NaN which I could not find in C conveniently.
I could not however find a function to classify if a NaN is sNaN or qNaN, so let's just print out the NaN raw bytes:
main.c...
How do I create an average from a Ruby array?
...
Try this:
arr = [5, 6, 7, 8]
arr.inject{ |sum, el| sum + el }.to_f / arr.size
=> 6.5
Note the .to_f, which you'll want for avoiding any problems from integer division. You can also do:
arr = [5, 6, 7, 8]
arr.inject(0.0) { |sum, el| sum + el } / arr.size
=> 6.5
You can define it...
Python decorators in classes
...
Would something like this do what you need?
class Test(object):
def _decorator(foo):
def magic( self ) :
print "start magic"
foo( self )
print "end magic"
return magic
@_decorator
def bar( self ) :
print "normal call"
test ...
PHP CURL DELETE request
...roblem, here is my solution:
I created a new method:
public function curl_del($path)
{
$url = $this->__url.$path;
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "DELETE");
$result = curl_exec($ch);
$httpCode = curl_getinfo...
split string only on first instance of specified character
In my code I split a string based on _ and grab the second item in the array.
17 Answers
...
Why doesn't Python have a sign function?
...y removed and replaced by sign! Have you never implemented a class with a __cmp__ method? Have you never called cmp and specified a custom comparator function?
In summary, I've found myself wanting a sign function too, but copysign with the first argument being 1 will work just fine. I disagree ...
C++0x has no semaphores? How to synchronize threads?
...ex and a condition variable:
#include <mutex>
#include <condition_variable>
class semaphore
{
private:
std::mutex mutex_;
std::condition_variable condition_;
unsigned long count_ = 0; // Initialized as locked.
public:
void notify() {
std::lock_guard<decltype...
Asynchronous method call in Python?
...an use pools of processes and then get results asynchronously with:
apply_async(func[, args[, kwds[, callback]]])
E.g.:
from multiprocessing import Pool
def f(x):
return x*x
if __name__ == '__main__':
pool = Pool(processes=1) # Start a worker processes.
result = pool....
error LNK2038: mismatch detected for '_ITERATOR_DEBUG_LEVEL': value '0' doesn't match value '2' in m
...al studio or they explicitly added the defines to the project.
Search for _ITERATOR_DEBUG_LEVEL and _SECURE_SCL remove them or set them appropriately in all projects and sources and rebuild everything.
_ITERATOR_DEBUG_LEVEL = 0 // disabled (for release builds)
_ITERATOR_DEBUG_LEVEL = 1 // enabled ...
How can I detect if the user is on localhost in PHP?
...
You can also use $_SERVER['REMOTE_ADDR'] for which IP address of the client requesting is given by the web server.
$whitelist = array(
'127.0.0.1',
'::1'
);
if(!in_array($_SERVER['REMOTE_ADDR'], $whitelist)){
// not valid
}
...