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How to read and write excel file
I want to read and write an Excel file from Java with 3 columns and N rows, printing one string in each cell. Can anyone give me simple code snippet for this? Do I need to use any external lib or does Java have built-in support for it?
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How do I create an empty array/matrix in NumPy?
...might be best off to keep it in a list until it is finished, and only then convert it into an array.
e.g.
mylist = []
for item in data:
mylist.append(item)
mat = numpy.array(mylist)
item can be a list, an array or any iterable, as long
as each item has the same number of elements.
In this ...
What is meant with “const” at end of function declaration? [duplicate]
...al function taking an implicit this pointer. So a method int Foo::Bar(int random_arg) (without the const at the end) results in a function like int Foo_Bar(Foo* this, int random_arg), and a call such as Foo f; f.Bar(4) will internally correspond to something like Foo f; Foo_Bar(&f, 4). Now addin...
Try-catch speeding up my code?
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One of the Roslyn engineers who specializes in understanding optimization of stack usage took a look at this and reports to me that there seems to be a problem in the interaction between the way the C# compiler generates local variable stores and the way the JIT compiler does re...
Expand/collapse section in UITableView in iOS
Could somebody tell me the way to perform UITableView expandable/collapsible animations in sections of UITableView as below?
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Capture screenshot of active window?
I am making a screen capturing application and everything is going fine. All I need to do is capture the active window and take a screenshot of this active window. Does anyone know how I can do this?
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C# 3.0 auto-properties — useful or not? [closed]
...code? If you want to do stuff in getters or setters, there's no problem to convert them to normal properties later on.
As you said you could use fields, and if you wanted to add logic to them later you'd convert them to properties. But this might present problems with any use of reflection (and pos...
What are the disadvantages to declaring Scala case classes?
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First the good bits:
Everything immutable by default
Yes, and can even be overridden (using var) if you need it
Getters automatically defined
Possible in any class by prefixing params with val
Decent toString() implementation
Yes, very useful, but doable by hand on any class if nece...
Best way to extract a subvector from a vector?
... +1, also it's O(Y-X), which is less than or equal to O(N) (and in his example much less)
– orip
Jan 7 '09 at 21:53
78
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What is the relative performance difference of if/else versus switch statement in Java?
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That's micro optimization and premature optimization, which are evil. Rather worry about readabililty and maintainability of the code in question. If there are more than two if/else blocks glued together or its size is unpredictable, then you may high...