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Loop backwards using indices in Python?
...as no way to tell the xrange to go backwards... (Since Python 2.6 it calls __reversed__().)
– Robert Siemer
Jun 21 '12 at 18:31
...
How do I import the Django DoesNotExist exception?
...mentation:
self.assertRaises(Answer.DoesNotExist, Answer.objects.get, body__exact='<p>User can reply to discussion.</p>')
or better:
with self.assertRaises(Answer.DoesNotExist):
Answer.objects.get(body__exact='<p>User can reply to discussion.</p>')
...
App Inventor 2 时间处理教程 - 时间戳转换、格式化与计算 · App Inventor 2 中文网
... = 计时器1.FormatDateTime(当前时间, "yyyy-MM-dd HH:mm:ss")
标签_时间.Text = 显示
}
实时更新
when Screen1.Initialize() {
计时器1.TimerInterval = 1000 // 1秒更新
计时器1.TimerEnabled = true
}
when 计时器1.Timer() {
var 当前时间 = 计...
Some built-in to pad a list in python
...
a += [''] * (N - len(a))
or if you don't want to change a in place
new_a = a + [''] * (N - len(a))
you can always create a subclass of list and call the method whatever you please
class MyList(list):
def ljust(self, n, fillvalue=''):
return self + [fillvalue] * (n - len(self))
a...
Understanding scala enumerations
...s. It is useful, because after you import it elsewhere with import WeekDay._, you can use that type, e.g.:
def isWorkingDay(d: WeekDay) = ! (d == Sat || d == Sun)
Instead, a minimal version would just be:
object WeekDay extends Enumeration {
val Mon, Tue, Wed, Thu, Fri, Sat, Sun = Value
}
an...
Reading a huge .csv file
...tly over getdata() in your code:
for row in getdata(somefilename, sequence_of_criteria):
# process row
You now only hold one row in memory, instead of your thousands of lines per criterion.
yield makes a function a generator function, which means it won't do any work until you start looping ...
Link to all Visual Studio $ variables
... on my machine. Probably not all macros are defined for others (e.g. OCTAVE_EXECUTABLE), but I wanted to err on the side of inclusiveness here.
For example, this is the first time that I see $(Language) (expanding to C++ for this project) being mentioned outside of the IDE.
$(AllowLocalNetworkLoop...
What happens to global and static variables in a shared library when it is dynamically linked?
...yntax similar to the function export/import syntax, i.e.:
#ifdef COMPILING_THE_DLL
#define MY_DLL_EXPORT extern "C" __declspec(dllexport)
#else
#define MY_DLL_EXPORT extern "C" __declspec(dllimport)
#endif
MY_DLL_EXPORT int my_global;
When you do that, the global variable is added to the list of...
What is the _references.js used for?
What is the _references.js file used for in a new ASP.NET MVC 4 project?
2 Answers
2
...
Detecting endianness programmatically in a C++ program
...e warned against by compiler. That's exactly what unions are for !
bool is_big_endian(void)
{
union {
uint32_t i;
char c[4];
} bint = {0x01020304};
return bint.c[0] == 1;
}
The principle is equivalent to the type case as suggested by others, but this is clearer - and...