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Best way to select random rows PostgreSQL
...lass WHERE oid = 'schema_name.big'::regclass;
As long as ct isn't much smaller than id_span, the query will outperform other approaches.
WITH params AS (
SELECT 1 AS min_id -- minimum id <= current min id
, 5100000 AS id_span -- rounded up. (max_id - m...
How do I add a margin between bootstrap columns without wrapping [duplicate]
... Sep 25 '13 at 17:00
Charles IngallsCharles Ingalls
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RSS Feeds in ASP.NET MVC
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Here is what I recommend:
Create a class called RssResult that
inherits off the abstract base class
ActionResult.
Override the ExecuteResult method.
ExecuteResult has the ControllerContext passed to it by the caller and with this you can get the data and content type...
Constants in Objective-C
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Overall, great answer, with one glaring caveat: you DO NOT want to test for string equality with the == operator in Objective-C, since it tests memory address. Always use -isEqualToString: for this. You can easily get a different...
How can I use pointers in Java?
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All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
pandas dataframe columns scaling with sklearn
...and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
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Pass an array of integers to ASP.NET Web API?
...iptor.GetConverter(elementType);
var values = Array.ConvertAll(s.Split(new[] { ","},StringSplitOptions.RemoveEmptyEntries),
x => { return converter.ConvertFromString(x != null ? x.Trim() : x); });
var typedValues = Array.CreateInstance(elementT...
Proper use of the IDisposable interface
... they will never be cleaned up. The garbage collector doesn't know how to call DeleteHandle() on a variable of type IntPtr, it doesn't know whether or not it needs to call DeleteHandle().
Note: What is an unmanaged resource? If you found it in the Microsoft .NET Framework: it's managed. If you w...
How can I get nth element from a list?
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Personally I can't comprehend how an at-index accessor that doesn't return a Maybe type is acceptable as idiomatic Haskell. [1,2,3]!!6 will give you a runtime error. It could very easily be avoided if !! had the type [a] -> Int ...
Best way to assert for numpy.array equality?
..._equal is more reliable.
update
A few versions ago numpy obtained assert_allclose which is now my favorite since it allows us to specify both absolute and relative error and doesn't require decimal rounding as the closeness criterion.
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