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What is more efficient? Using pow to square or just multiply it with itself?
What of these two methods is in C more efficient? And how about:
7 Answers
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LEFT OUTER joins in Rails 3
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what if you only wanted the Posts which had no user?
– mcr
Aug 18 '11 at 4:30
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What's better at freeing memory with PHP: unset() or $var = null
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It was mentioned in the unset manual's page in 2009:
unset() does just what its name says - unset a variable. It does not force immediate memory freeing. PHP's garbage collector will do it when it see fits - by intention as soon, as those CPU cycles aren't needed anyway, or as late as before the...
How to call an external command?
... recommend using them directly.
The subprocess module should probably be what you use.
Finally please be aware that for all methods where you pass the final command to be executed by the shell as a string and you are responsible for escaping it. There are serious security implications if any part...
Check if the number is integer
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What's wrong with as.integer(x) == x? It will not reject 3 or 3.0 like is.integer(x) would, and it will catch 3.1.
– Gabi
Oct 1 '15 at 19:04
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What is the best way to concatenate two vectors?
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This is precisely what the member function std::vector::insert is for
std::vector<int> AB = A;
AB.insert(AB.end(), B.begin(), B.end());
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What does Serializable mean?
What exactly does it mean for a class to be Serializable in Java? Or in general, for that matter...
10 Answers
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What are the benefits to marking a field as `readonly` in C#?
What are the benefits of having a member variable declared as read only? Is it just protecting against someone changing its value during the lifecycle of the class or does using this keyword result in any speed or efficiency improvements?
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What is the difference between square brackets and parentheses in a regex?
... that regex is trying to match << or >> or [[ or ]]. But from what you've said, it should be matching < or > or [ or ]. If you use | between [], do the brackets behave differently?
– Daniel Kaplan
Nov 14 '17 at 20:39
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What exactly does big Ө notation represent?
...s Ө(n), then there is some constant k, such that your function (run-time, whatever), is larger than n*k for sufficiently large n, and some other constant K such that your function is smaller than n*K for sufficiently large n.
In other words, for sufficiently large n, it is sandwiched between two...