大约有 42,000 项符合查询结果（耗时：0.0407秒） [XML]
Why is there huge performance hit in 2048x2048 versus 2047x2047 array multiplication?
...L is always power of 2.
The six comes from fact that 2^6 == 64 bytes is standard size of cache line.
Now what does this mean? Well it means that if I have address X and address Y and
(X >> 6) - (Y >> 6) is divisible by L (i.e. some large power of 2), they will be stored in the same ca...
What's the deal with a leading underscore in PHP class methods?
...of Object Oriented PHP (PHP 4). That implementation of OO was pretty bad, and didn't include things like private methods. To compensate, PHP developers prefaced methods that were intended to be private with an underscore. In some older classes you'll see /**private*/ __foo() { to give it some ext...
What is a race condition?
...
A race condition occurs when two or more threads can access shared data and they try to change it at the same time. Because the thread scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the re...
C# DLL config file
...
It is not trivial to create a .NET configuration file for a .DLL, and for good reason. The .NET configuration mechanism has a lot of features built into it to facilitate easy upgrading/updating of the app, and to protect installed apps from trampling each others configuration files.
There...
Step-by-step debugging with IPython
...
You can use IPython's %pdb magic. Just call %pdb in IPython and when an error occurs, you're automatically dropped to ipdb. While you don't have the stepping immediately, you're in ipdb afterwards.
This makes debugging individual functions easy, as you can just load a file with %load...
Handling exceptions from Java ExecutorService tasks
...her
explicitly or via methods such as
submit, these task objects catch and
maintain computational exceptions, and
so they do not cause abrupt
termination, and the internal
exceptions are not passed to this
method.
When you submit a Runnable, it'll get wrapped in a Future.
Your after...
What does this thread join code mean?
In this code, what does the two joins and break mean? t1.join() causes t2 to stop until t1 terminates?
10 Answers
...
Difference between viewDidLoad and viewDidAppear
What is the difference between viewDidLoad and viewDidAppear ? What kind of initialization or custom code goes into those functions?
...
What is a NullPointerException, and how do I fix it?
What are Null Pointer Exceptions ( java.lang.NullPointerException ) and what causes them?
12 Answers
...
Why doesn't Python have a sign function?
I can't understand why Python doesn't have a sign function. It has an abs builtin (which I consider sign 's sister), but no sign .
...