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Java: when to use static methods
I am wondering when to use static methods? Say if I have a class with a few getters and setters, a method or two, and I want those methods only to be invokable on an instance object of the class. Does this mean I should use a static method?
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Java Programming - Where should SQL statements be stored? [closed]
Where should an JDBC-compliant application store its SQL statements and why?
15 Answers
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When would you use a WeakHashMap or a WeakReference?
The use of weak references is something that I've never seen an implementation of so I'm trying to figure out what the use case for them is and how the implementation would work. When have you needed to use a WeakHashMap or WeakReference and how was it used?
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Is there a performance impact when calling ToList()?
When using ToList() , is there a performance impact that needs to be considered?
8 Answers
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how does multiplication differ for NumPy Matrix vs Array classes?
The numpy docs recommend using array instead of matrix for working with matrices. However, unlike octave (which I was using till recently), * doesn't perform matrix multiplication, you need to use the function matrixmultipy(). I feel this makes the code very unreadable.
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vector::at vs. vector::operator[]
I know that at() is slower than [] because of its boundary checking, which is also discussed in similar questions like C++ Vector at/[] operator speed or ::std::vector::at() vs operator[] << surprising results!! 5 to 10 times slower/faster! . I just don't understand what the at() met...
Why isn't Python very good for functional programming? [closed]
I have always thought that functional programming can be done in Python. Thus, I was surprised that Python didn't get much of a mention in this question, and when it was mentioned, it normally wasn't very positive. However, not many reasons were given for this (lack of pattern matching and algebra...
Is there a difference between foreach and map?
Ok this is more of a computer science question, than a question based on a particular language, but is there a difference between a map operation and a foreach operation? Or are they simply different names for the same thing?
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What are the differences between “=” and “
What are the differences between the assignment operators = and <- in R?
7 Answers
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How do I parse an ISO 8601-formatted date?
I need to parse RFC 3339 strings like "2008-09-03T20:56:35.450686Z" into Python's datetime type.
27 Answers
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