大约有 40,000 项符合查询结果(耗时:0.0506秒) [XML]

https://stackoverflow.com/ques... 

Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?

...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
https://stackoverflow.com/ques... 

Check if a number is int or float

...>> if isinstance(x, int): print 'x is a int!' x is a int! _EDIT:_ As pointed out, in case of long integers, the above won't work. So you need to do: >>> x = 12L >>> import numbers >>> isinstance(x, numbers.Integral) True >>> isinstance(x, int) F...
https://stackoverflow.com/ques... 

Razor-based view doesn't see referenced assemblies

...m another project in the same solution (with assembly name MyCoreDBLayer). All objects from MyCore.DBLayer worked perfectly in Controllers and Models but failed in Razor views with an error 'The type or namespace name 'DBLayer' does not exist in the namespace 'MyCore' (are you missing an assembly re...
https://stackoverflow.com/ques... 

When is std::weak_ptr useful?

...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer. But what if that object is in use and some other code holds a s...
https://stackoverflow.com/ques... 

How do I run Python code from Sublime Text 2?

... find out where your Break key is here: http://en.wikipedia.org/wiki/Break_key. Note: CTRL + C will NOT work. What to do when Ctrl + Break does not work: Go to: Preferences -> Key Bindings - User and paste the line below: {"keys": ["ctrl+shift+c"], "command": "exec", "args": {"k...
https://stackoverflow.com/ques... 

When should you use constexpr capability in C++11?

... "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there? ...
https://stackoverflow.com/ques... 

Remove duplicate dict in list in Python

... {'a': 3222, 'b': 1234}, {'a': 123, 'b': 1234}] seen = set() new_l = [] for d in l: t = tuple(d.items()) if t not in seen: seen.add(t) new_l.append(d) print new_l Example output: [{'a': 123, 'b': 1234}, {'a': 3222, 'b': 1234}] Note: As pointed out by @alexis ...
https://stackoverflow.com/ques... 

Could not load NIB in bundle

... Additionally, if you are using alloc init, instead of initWithNibName:bunle:, what you will get is a black screen. – Robert Childan Apr 20 '12 at 8:36 ...
https://stackoverflow.com/ques... 

What is a bus error?

... when your processor cannot even attempt the memory access requested, typically: using a processor instruction with an address that does not satisfy its alignment requirements. Segmentation faults occur when accessing memory which does not belong to your process, they are very common and are typ...
https://stackoverflow.com/ques... 

Functional programming - is immutability expensive? [closed]

...’d like to clarify some points. The “in-place” quicksort isn’t really in-place (and quicksort is not by definition in-place). It requires additional storage in the form of stack space for the recursive step, which is in the order of O(log n) in the best case, but O(n) in the worst case. Im...