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What is a mixin, and why are they useful?
... and `==`,
but this class does NOT implement those methods."""
def __ne__(self, other):
return not (self == other)
def __lt__(self, other):
return self <= other and (self != other)
def __gt__(self, other):
return not self <= other
def __ge__(self, ot...
Minimizing NExpectation for a custom distribution in Mathematica
.... Let's extract it from your definition above into simple functions:
pdf[a_, b_, m_, s_, x_] := (1/(2*(a + b)))*a*b*
(E^(a*(m + (a*s^2)/2 - x))*Erfc[(m + a*s^2 - x)/(Sqrt[2]*s)] +
E^(b*(-m + (b*s^2)/2 + x))*Erfc[(-m + b*s^2 + x)/(Sqrt[2]*s)])
pdf2[a_, b_, m_, s_, x_] := pdf[a, b, m, s, Log...
[精华]VC++对话框程序打印及打印预览的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...程序文件菜单中会生成两个菜单项分别是打印（标识符ID_FILE_PRINT）和打印预览(标识符：ID_FILE_PRINT_PREVIEW)，展开程序源代码，可以发现，是CVIEW类提供标准打印和打印预览菜单命令的消息处理函数：
设应用程序视图类为CMyView,展...
How to split a string literal across multiple lines in C / Objective-C?
...ll lines in C can be split into multiple lines using \.
Plain C:
char *my_string = "Line 1 \
Line 2";
Objective-C:
NSString *my_string = @"Line1 \
Line2";
Better approach
There's a better approach that works just for strings.
Plain C:
char *my_str...
Is it possible to make the -init method private in Objective-C?
...
NS_UNAVAILABLE
- (instancetype)init NS_UNAVAILABLE;
This is a the short version of the unavailable attribute. It first appeared in macOS 10.7 and iOS 5. It is defined in NSObjCRuntime.h as #define NS_UNAVAILABLE UNAVAILABLE_...
AngularJS HTTP post to PHP and undefined
... data value to pass an appropriate query string, so PHP is not populating $_POST as you expect.
My suggestion would be to just use the default angularjs setting of application/json as header, read the raw input in PHP, and then deserialize the JSON.
That can be achieved in PHP like this:
$postdat...
How to flush output of print function?
.../python3 to #!/usr/bin/python3 -u - now when you run your script (e.g. ./my_script.py) the -u will always be added for you
– James
Sep 7 at 17:22
add a comment
...
Label Alignment in iOS 6 - UITextAlignment deprecated
...f UITextAlignmentCenter and a list of other replacements is below:
#ifdef __IPHONE_6_0 // iOS6 and later
# define UITextAlignmentCenter NSTextAlignmentCenter
# define UITextAlignmentLeft NSTextAlignmentLeft
# define UITextAlignmentRight NSTextAlignmentRight
# define UILineBreakM...
How to compare type of an object in Python?
...
isinstance works:
if isinstance(obj, MyClass): do_foo(obj)
but, keep in mind: if it looks like a duck, and if it sounds like a duck, it is a duck.
EDIT: For the None type, you can simply do:
if obj is None: obj = MyClass()
...
How to write header row with csv.DictWriter?
...od now available in 2.7 / 3.2:
from collections import OrderedDict
ordered_fieldnames = OrderedDict([('field1',None),('field2',None)])
with open(outfile,'wb') as fou:
dw = csv.DictWriter(fou, delimiter='\t', fieldnames=ordered_fieldnames)
dw.writeheader()
# continue on to write data
...