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Multiple aggregations of the same column using pandas GroupBy.agg()
...g functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
3 Answers
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What are 'get' and 'set' in Swift?
...re the code:
In addition to simple properties that are stored, properties can have a getter and a setter.
class EquilateralTriangle: NamedShape {
...
When some other class wants to get that perimeter variable, they do this:
let someVar = myTriangle.perimeter
... Which calls this:
get{
r...
Does setting Java objects to null do anything anymore?
I was browsing some old books and found a copy of "Practical Java" by Peter Hagger. In the performance section, there is a recommendation to set object references to null when no longer needed.
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Can you help me understand Moq Callback?
Using Moq and looked at Callback but I have not been able to find a simple example to understand how to use it.
5 Answers...
Why do I need Transaction in Hibernate for read-only operations?
...ndeed strange and often people don't mark methods for transactions in this case. But JDBC will create transaction anyway, it's just it will be working in autocommit=true if different option wasn't set explicitly.
But there is no guarantee that your method doesn't write into the database. If you mark...
combinations between two lists?
...having trouble wrapping my head around a algorithm I’m try to make. Basically, I have two lists and want to get all the combinations of the two lists.
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Memory management in Qt?
...I need to delete and/or destroy my objects? Is any of this handled automatically?
4 Answers
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Verifying a specific parameter with Moq
...viceClient is receiving the right parameter, which is an XmlElement, but I can't find any way to make it work. It works only when I don't check a particular value.
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Why Func instead of Predicate?
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While Predicate has been introduced at the same time that List<T> and Array<T>, in .net 2.0, the different Func and Action variants come from .net 3.5.
So those Func predicates are used mainly for consistency in the LINQ op...
What are fixtures in programming?
...nment in which tests are run so that results are
repeatable. Some people call this the test context.
Examples of fixtures:
Loading a database with a specific, known set of data
Erasing a hard disk and installing a known clean operating system installation
Copying a specific known ...