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What's the difference between & and && in MATLAB?
What is the difference between the & and && logical operators in MATLAB?
7 Answers
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Append an object to a list in R in amortized constant time, O(1)?
If I have some R list mylist , you can append an item obj to it like so:
17 Answers
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How to implement a queue with three stacks?
I came across this question in an algorithms book ( Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne).
5 Answ...
Callback functions in Java
Is there a way to pass a call back function in a Java method?
17 Answers
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In Javascript, how to conditionally add a member to an object?
I would like to create an object with a member added conditionally.
The simple approach is:
22 Answers
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Get records with max value for each group of grouped SQL results
... a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. The solution is to first order the ...
Difference between declaring variables before or in loop?
I have always wondered if, in general, declaring a throw-away variable before a loop, as opposed to repeatedly inside the loop, makes any (performance) difference?
A (quite pointless) example in Java:
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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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SQL JOIN and different types of JOINs
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TylerH
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answered Nov 30 '13 at 9:34
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Does JavaScript have “Short-circuit” evaluation?
...rcuit" evaluation.
if (true == true || foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
if (false && foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
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