大约有 13,700 项符合查询结果（耗时：0.0363秒） [XML]
How do I achieve the theoretical maximum of 4 FLOPs per cycle?
...m>
using namespace std;
typedef unsigned long long uint64;
double test_dp_mac_SSE(double x,double y,uint64 iterations){
register __m128d r0,r1,r2,r3,r4,r5,r6,r7,r8,r9,rA,rB,rC,rD,rE,rF;
// Generate starting data.
r0 = _mm_set1_pd(x);
r1 = _mm_set1_pd(y);
r8 = _mm_set1_pd(...
xtree(1796): warning C4800: “int”: 将值强制为布尔值“true”或“false...
...e\xtree(1775): 参见对正在编译的函数 模板 实例化“std::pair<_Ty1,_Ty2> std::_Tree<_Traits>::_Insert_nohint<std::pair<const _Kty,_Ty>&,_Nodety>(bool,_Valty,_Nodety)”的引用
1> with
1> [
1> _Ty1=std::_Tree_iterator<std::_Tree_val<std::_Tree_simple_t...
How to print instances of a class using print()?
...
>>> class Test:
... def __repr__(self):
... return "Test()"
... def __str__(self):
... return "member of Test"
...
>>> t = Test()
>>> t
Test()
>>> print(t)
member of Test
The __str__ method is what h...
What is the fastest way to get the value of π?
...ically, I'm using ways that don't involve using #define constants like M_PI , or hard-coding the number in.
22 Answers
...
Python __str__ and lists
...
Calling string on a python list calls the __repr__ method on each element inside. For some items, __str__ and __repr__ are the same. If you want that behavior, do:
def __str__(self):
...
def __repr__(self):
return self.__str__()
...
What is the __del__ method, How to call it?
I am reading a code. There is a class in which __del__ method is defined. I figured out that this method is used to destroy an instance of the class. However, I cannot find a place where this method is used. The main reason for that is that I do not know how this method is used, probably not like ...
Compare object instances for equality by their attributes
...
You should implement the method __eq__:
class MyClass:
def __init__(self, foo, bar):
self.foo = foo
self.bar = bar
def __eq__(self, other):
if not isinstance(other, MyClass):
# don't attempt to compare against ...
Should __init__() call the parent class's __init__()?
...
In Python, calling the super-class' __init__ is optional. If you call it, it is then also optional whether to use the super identifier, or whether to explicitly name the super class:
object.__init__(self)
In case of object, calling the super method is not st...
Relative imports in Python 2.7
...
Naming
When a file is loaded, it is given a name (which is stored in its __name__ attribute). If it was loaded as the top-level script, its name is __main__. If it was loaded as a module, its name is the filename, preceded by the names of any packages/subpackages of which it is a part, separated...
Is there a Python caching library?
...
From Python 3.2 you can use the decorator @lru_cache from the functools library.
It's a Last Recently Used cache, so there is no expiration time for the items in it, but as a fast hack it's very useful.
from functools import lru_cache
@lru_cache(maxsize=256)
def f(x):
...