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How to write inline if statement for print?
... condition:
block
if expression (introduced in Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly ...
How to lock orientation during runtime
...
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
Called on an activity, will lock it to landscape. Look for the other flags in the ActivityInfo class. You can lock it back to portrait or make it sensor/slider driven.
More info here: http://www....
Get original URL referer with PHP?
I am using $_SERVER['HTTP_REFERER']; to get the referer Url. It works as expected until the user clicks another page and the referer changes to the last page.
...
Copy constructor for a class with unique_ptr
How do I implement a copy constructor for a class that has a unique_ptr member variable? I am only considering C++11.
6 A...
Synchronous request in Node.js
...and pass to the next
endpoints =
[{ host: 'www.example.com', path: '/api_1.php' },
{ host: 'www.example.com', path: '/api_2.php' },
{ host: 'www.example.com', path: '/api_3.php' }];
async.mapSeries(endpoints, http.get, function(results){
// Array of results
});
...
What does enumerate() mean?
What does for row_number, row in enumerate(cursor): do in Python?
5 Answers
5
...
In Python, how do I index a list with another list?
...ng, either by integer, slice or index-list:
class Flexlist(list):
def __getitem__(self, keys):
if isinstance(keys, (int, slice)): return list.__getitem__(self, keys)
return [self[k] for k in keys]
Which, for your example, you would use as:
L = Flexlist(['a', 'b', 'c', 'd', 'e...
Scala: List[Future] to Future[List] disregarding failed futures
...
def futureToFutureTry[T](f: Future[T]): Future[Try[T]] =
f.map(Success(_)).recover { case x => Failure(x)}
val listOfFutures = ...
val listOfFutureTrys = listOfFutures.map(futureToFutureTry(_))
Then use Future.sequence as before, to give you a Future[List[Try[T]]]
val futureListOfTrys = F...
How to use timeit module
... you defined earlier during the interactive session by importing them from __main__ in the setup statement:
>>> def f(x):
... return x * x
...
>>> import timeit
>>> timeit.repeat("for x in range(100): f(x)", "from __main__ import f",
number=100000)...
Is there a benefit to defining a class inside another class in Python?
... use a metaclass, it's sometimes handy to do
class Foo(object):
class __metaclass__(type):
....
instead of defining a metaclass separately, if you're only using it once.
The only other time I've used nested classes like that, I used the outer class only as a namespace to group a bun...