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How to identify numpy types in python?
...hing in numpy.* you just walk the parent package of the module. (At that point, you obviously want to wrap it in a function.) And if you want pandas DataFrames to count as numpyish, add an or to test for that. And so on. The point is, you have to know what you're actually asking for when you want to...
How to set margin of ImageView using code, not xml
... What's the deal w/ the last 2 lines? clone the margin params into another params variable? I can confirm it's required :)
– Adam Rabung
Sep 1 '11 at 13:06
1
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C: What is the difference between ++i and i++?
...t the generated code, which will be identical.
The efficiency question is interesting... here's my attempt at an answer:
Is there a performance difference between i++ and ++i in C?
As @OnFreund notes, it's different for a C++ object, since operator++() is a function and the compiler can't know to ...
How to get all subsets of a set? (powerset)
... is 2 ** len(A), so that could clearly be seen in the for loop.
I need to convert the input (ideally a set) into a list because by a set is a data structure of unique unordered elements, and the order will be crucial to generate the subsets.
selector is key in this algorithm. Note that selector ha...
What is the “right” JSON date format?
...is a non-standard hack/extension.
I would use a format that can be easily converted to a Date object in JavaScript, i.e. one that can be passed to new Date(...). The easiest and probably most portable format is the timestamp containing milliseconds since 1970.
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How does a ArrayList's contains() method evaluate objects?
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ArrayList implements the List Interface.
If you look at the Javadoc for List at the contains method you will see that it uses the equals() method to evaluate if two objects are the same.
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SQL to determine minimum sequential days of access?
...s OR UserId = 52551
EDIT:
Okay here's my serious answer:
DECLARE @days int
DECLARE @seconds bigint
SET @days = 30
SET @seconds = (@days * 24 * 60 * 60) - 1
SELECT DISTINCT UserId
FROM (
SELECT uh1.UserId, Count(uh1.Id) as Conseq
FROM UserHistory uh1
INNER JOIN UserHistory uh2 ON uh2....
Syntax of for-loop in SQL Server
...
It interesting to note the the MS documentation is wrong here, really. WHILE doesn't take a boolean expression - it takes a predicate - which in addition to being able to evaluate to TRUE or FALSE, could also be UNKNOWN.
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How expensive is RTTI?
...ource usage in common implementations.
I recently did a bunch of research into RTTI in GCC.
tl;dr: RTTI in GCC uses negligible space and typeid(a) == typeid(b) is very fast, on many platforms (Linux, BSD and maybe embedded platforms, but not mingw32). If you know you'll always be on a blessed plat...
How to get position of a certain element in strings vector, to use it as an index in ints vector?
...ment in a vector of strings , to use it as an index in another vector of int type, is this possible ?
3 Answers
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