大约有 40,000 项符合查询结果（耗时：0.0476秒） [XML]
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
I just discovered a logical bug in my code which was causing all sorts of problems. I was inadvertently doing a bitwise AND instead of a logical AND .
...
Django, creating a custom 500/404 error page
... for some reason request.user appears fine in the 404 template, but not at all in the 500 template (and they are almost identical) -- posted question on this here: stackoverflow.com/questions/26043211/…
– Gravity Grave
Sep 25 '14 at 16:13
...
'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
...
and tests whether both expressions are logically True while & (when used with True/False values) tests if both are True.
In Python, empty built-in objects are typically treated as logically False while non-empty built-ins are logically True. This facilitates the c...
How to use single storyboard uiviewcontroller for multiple subclass
...do what you propose because there are no initializers in UIStoryboard that allow overriding the view controller associated with the storyboard as defined in the object details in the storyboard on initialization. It's at initialization that all the UI elements in the stoaryboard are linked up to th...
How to list the contents of a package using YUM?
...
There is a package called yum-utils that builds on YUM and contains a tool called repoquery that can do this.
$ repoquery --help | grep -E "list\ files"
-l, --list list files in this package/group
Combined into one example:
$ r...
What is the difference between char array and char pointer in C?
...char* and char[] are different types, but it's not immediately apparent in all cases. This is because arrays decay into pointers, meaning that if an expression of type char[] is provided where one of type char* is expected, the compiler automatically converts the array into a pointer to its first el...
TypeScript static classes
...hat cannot be subclassed and must contain only static methods. C# does not allow one to define functions outside of classes. In TypeScript this is possible, however.
If you're looking for a way to put your functions/methods in a namespace (i.e. not global), you could consider using TypeScript's mod...
'uint32_t' identifier not found error
...
On Windows I usually use windows types. To use it you have to include <Windows.h>.
In this case uint32_t is UINT32 or just UINT.
All types definitions are here: http://msdn.microsoft.com/en-us/library/windows/desktop/aa383751%28v=vs....
Printing without newline (print 'a',) prints a space, how to remove?
... This will consume a bit of memory for the string, but only make a single call to print. Note that string concatenation using += is now linear in the size of the string you're concatenating so this will be fast.
>>> for i in xrange(20):
... s += 'a'
...
>>> print s
aaaaaaaaaa...
Django : How can I see a list of urlpatterns?
...
If you want a list of all the urls in your project, first you need to install django-extensions, add it to your settings like this:
INSTALLED_APPS = (
...
'django_extensions',
...
)
And then, run this command in your terminal
./manage.py show_...