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Meaning of “[: too many arguments” error from if [] (square brackets)
...t find any one simple straightforward resource spelling out the meaning of and fix for the following BASH shell error, so I'm posting what I found after researching it.
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How do I integrate Ajax with Django applications?
I am new to Django and pretty new to Ajax. I am working on a project where I need to integrate the two. I believe that I understand the principles behind them both, but have not found a good explanation of the two together.
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How to optimize for-comprehensions and loops in Scala?
...imizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catch is expensive. But since such nested returns are rare in Scala programs, the optimizer did not yet address this case. There is work going on to improve the optimizer which hopefully will solve this issue soon.
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Switch on ranges of integers in JavaScript [duplicate]
... than five");
break;
case (x < 9):
alert("between 5 and 8");
break;
case (x < 12):
alert("between 9 and 11");
break;
default:
alert("none");
break;
}
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How to select the first element with a specific attribute using XPath
...n 17 '09 at 10:48
Jonathan FinglandJonathan Fingland
52k1111 gold badges7979 silver badges7777 bronze badges
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What's the simplest way to test whether a number is a power of 2 in C++?
...will want to check for it explicitly.
http://www.graphics.stanford.edu/~seander/bithacks.html has a large collection of clever bit-twiddling algorithms, including this one.
share
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improve this ans...
Using LIMIT within GROUP BY to get N results per group?
...T aggregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
Are soft deletes a good idea? [duplicate]
... to include a WHERE IsDeleted = false clause in every query on this table (and so much worse if you're JOINing these tables). A mistake here would be caught as soon as a user or tester noticed a deleted record showing up again, which might take some time. Also, it would be easy for a developer to ...
How to find the kth largest element in an unsorted array of length n in O(n)?
...
This is called finding the k-th order statistic. There's a very simple randomized algorithm (called quickselect) taking O(n) average time, O(n^2) worst case time, and a pretty complicated non-randomized algorithm (called introselect) taking O(n) worst case time. There's some info on Wikipedia, bu...
What is an idempotent operation?
...g that x in the mathematical definition represents the state of an object, and f is an operation that may mutate that object. For example, consider the Python set and its discard method. The discard method removes an element from a set, and does nothing if the element does not exist. So:
my_set.dis...