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Convert datetime object to a String of date only in Python
... see a lot on converting a date string to an datetime object in Python, but I want to go the other way.
I've got
11 An...
How can I produce an effect similar to the iOS 7 blur view?
...backgroundColor = [UIColor clearColor];
UIToolbar* bgToolbar = [[UIToolbar alloc] initWithFrame:myView.frame];
bgToolbar.barStyle = UIBarStyleDefault;
[myView.superview insertSubview:bgToolbar belowSubview:myView];
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What does the star operator mean, in a function call?
...ues = (1, 2)
s = sum(*values)
This will unpack the tuple so that it actually executes as:
s = sum(1, 2)
The double star ** does the same, only using a dictionary and thus named arguments:
values = { 'a': 1, 'b': 2 }
s = sum(**values)
You can also combine:
def sum(a, b, c, d):
return a ...
Send file using POST from a Python script
Is there a way to send a file using POST from a Python script?
8 Answers
8
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What __init__ and self do on Python?
...to declare it explicitly. When you create an instance of the A class and call its methods, it will be passed automatically, as in ...
a = A() # We do not pass any argument to the __init__ method
a.method_a('Sailor!') # We only pass a single argument
The __init__ method is roughly w...
NULL vs nullptr (Why was it replaced?) [duplicate]
...problem" of my answer, plus it's a nice reference. This answer is just a small part of the reasons.
– Cheers and hth. - Alf
Dec 11 '13 at 3:22
1
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Is it possible to have multiple statements in a python lambda expression?
...Q. Can you put multiple statements in a lambda?
A. No. But you don't actually need to use a lambda. You can put the statements in a def instead. i.e.:
def second_lowest(l):
l.sort()
return l[1]
map(second_lowest, lst)
Q. Can you get the second lowest item from a lambda by sorting the ...
How do I make class methods / properties in Swift?
...
They are called type properties and type methods and you use the class or static keywords.
class Foo {
var name: String? // instance property
static var all = [Foo]() // static type property
class var comp: In...
How to get all subsets of a set? (powerset)
...owerset([4, 5, 6])))
Using yield means that you do not need to calculate all results in a single piece of memory. Precalculating the masks outside the main loop is assumed to be a worthwhile optimization.
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OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
...e I was unable to find a relevant implementation I decided to accept the challenge.
I made some modifications to the squares demo present in OpenCV and the resulting C++ code below is able to detect a sheet of paper in the image:
void find_squares(Mat& image, vector<vector<Point> >...