大约有 40,000 项符合查询结果（耗时：0.0419秒） [XML]
Random number generation in C++11: how to generate, how does it work? [closed]
... MyRNG; // the Mersenne Twister with a popular choice of parameters
uint32_t seed_val; // populate somehow
MyRNG rng; // e.g. keep one global instance (per thread)
void initialize()
{
rng.seed(seed_val);
}
Now we can create distributions:
std::uniform_int_distribu...
How to call a Parent Class's method from Child Class in Python?
... for calling parent method.
If Foo class inherits from Bar, then from Bar.__init__ can be invoked from Foo via super().__init__():
class Foo(Bar):
def __init__(self, *args, **kwargs):
# invoke Bar.__init__
super().__init__(*args, **kwargs)
...
Rails: fields_for with index?
...s there a method (or way to pull off similar functionality) to do a fields_for_with_index ?
9 Answers
...
Object comparison in JavaScript [duplicate]
...
Unfortunately there is no perfect way, unless you use _proto_ recursively and access all non-enumerable properties, but this works in Firefox only.
So the best I can do is to guess usage scenarios.
1) Fast and limited.
Works when you have simple JSON-style objects without m...
Better way to cast object to int
... to signify a Nullable<int>. The "as" operator works like Convert.To____(), but think TryParse() rather than Parse(): it returns null rather than throwing an exception if the conversion fails.
Of these, I would prefer (int) if the object really is just a boxed integer. Otherwise use Conver...
New self vs. new static
...the first method, whereas static is bound to the called class (also see get_called_class()).
class A {
public static function get_self() {
return new self();
}
public static function get_static() {
return new static();
}
}
class B extends A {}
echo get_class(B::ge...
Python nonlocal statement
...so that it looks more like the idioms of languages with closures.
def make_counter():
count = 0
def counter():
nonlocal count
count += 1
return count
return counter
Obviously, you could write this as a generator, like:
def counter_generator():
count = 0
...
top -c command in linux to filter processes listed based on processname
... to get pid's of matching command lines:
top -c -p $(pgrep -d',' -f string_to_match_in_cmd_line)
top -p expects a comma separated list of pids so we use -d',' in pgrep. The -f flag in pgrep makes it match the command line instead of program name.
...
Bash continuation lines
...here document. (Line terminators will still remain, though.)
cat <<-____HERE
continuation
lines
____HERE
See also http://ss64.com/bash/syntax-here.html
If you need to preserve some, but not all, leading whitespace, you might use something like
sed 's/^ //' <<____HERE
Th...
How can you dynamically create variables via a while loop? [duplicate]
...uvwxyz')
print '\n'.join(repr(u) for u in globals() if not u.startswith('__'))
for i in xrange(8):
globals()[''.join(random.sample(alphabet,random.randint(3,26)))] = random.choice(alphabet)
print
print '\n'.join(repr((u,globals()[u])) for u in globals() if not u.startswith('__'))
one resu...