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What is “vectorization”?
Several times now, I've encountered this term in matlab, fortran ... some other ... but I've never found an explanation what does it mean, and what it does? So I'm asking here, what is vectorization, and what does it mean for example, that "a loop is vectorized" ?
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Is it better in C++ to pass by value or pass by constant reference?
Is it better in C++ to pass by value or pass by constant reference?
10 Answers
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What is the function __construct used for?
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__construct was introduced in PHP5 and it is the right way to define your, well, constructors (in PHP4 you used the name of the class for a constructor).
You are not required to define a constructor in your class, but if you wish to pass any parameters on object cons...
How do C++ class members get initialized if I don't do it explicitly?
... crname and age . What happens if I don't initialize them myself? Here is an example:
8 Answers
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How to Deal with Temporary NSManagedObject instances?
...ome stuff with them and then trash them or store to sqlite db. The problem is, I cannot create instances of NSManagedObject unconnected to NSManagedObjectContext and this means I have to clear up somehow after I decide that I don't need some of the objects in my db.
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Better to 'try' something and catch the exception or test if it's possible first to avoid an excepti
Should I test if something is valid or just try to do it and catch the exception?
8 Answers
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select * vs select column
...and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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Performance of Arrays vs. Lists
Say you need to have a list/array of integers which you need iterate frequently, and I mean extremely often. The reasons may vary, but say it's in the heart of the inner most loop of a high volume processing.
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Does use of final keyword in Java improve the performance?
...va we see lots of places where the final keyword can be used but its use is uncommon.
13 Answers
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Why do you need to put #!/bin/bash at the beginning of a script file?
..., you might see #!/bin/perl or #!/bin/perl5.
PS:
The exclamation mark (!) is affectionately called "bang". The shell comment symbol (#) is sometimes called "hash".
PPS:
Remember - under *nix, associating a suffix with a file type is merely a convention, not a "rule". An executable can be a binar...