大约有 30,000 项符合查询结果（耗时：0.0416秒） [XML]
What is the point of function pointers?
...
Most examples boil down to callbacks: You call a function f() passing the address of another function g(), and f() calls g() for some specific task. If you pass f() the address of h() instead, then f() will call back h() instead.
Basically, this is a...
How can bcrypt have built-in salts?
...s encrypted with a key generated from the: cost, salt and the password. we call that encrypted value the cipher text. then we attach the salt to this value and encoding it using base64. attaching the cost to it and this is the produced string from bcrypt:
$2a$COST$BASE64
This value is stored event...
Full Screen DialogFragment in Android
...api when testing.
public class FragmentDialog extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button button = (Button) findViewById(R.id.show);
button.setOnClickListener(new OnCl...
Wrapping a C library in Python: C, Cython or ctypes?
I want to call a C library from a Python application. I don't want to wrap the whole API, only the functions and datatypes that are relevant to my case. As I see it, I have three choices:
...
What is the use of join() in Python threading?
...at clumsy ascii-art to demonstrate the mechanism:
The join() is presumably called by the main-thread. It could also be called by another thread, but would needlessly complicate the diagram.
join-calling should be placed in the track of the main-thread, but to express thread-relation and keep it as ...
What is the difference between an expression and a statement in Python?
...rs, where operators include arithmetic and boolean operators, the function call operator () the subscription operator [] and similar, and can be reduced to some kind of "value", which can be any Python object. Examples:
3 + 5
map(lambda x: x*x, range(10))
[a.x for a in some_iterable]
yield 7
Sta...
What does numpy.random.seed(0) do?
...thing every time you run it.
To get the most random numbers for each run, call numpy.random.seed(). This will cause numpy to set the seed to a random number obtained from /dev/urandom or its Windows analog or, if neither of those is available, it will use the clock.
For more information on using ...
R script line numbers at error?
...you the line number, but it will tell you where the failure happens in the call stack which is very helpful:
traceback()
[Edit:] When running a script from the command line you will have to skip one or two calls, see traceback() for interactive and non-interactive R sessions
I'm not aware of ano...
Detecting when the 'back' button is pressed on a navbar
...wController has TRUE value when I'm poping the navigation stack programmatically using popToRootViewControllerAnimated - without any touch on the back button. Should I downvote your answer? (the subject says "'back' button is pressed on a navbar")
– kas-kad
Jan...
“Java DateFormat is not threadsafe” what does this leads to?
...Java DateFormat not being thread safe and I understand the concept theoretically.
11 Answers
...