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Find nearest latitude/longitude with an SQL query
...startlng] - longitude) * COS(latitude / 57.3), 2)) AS distance
FROM TableName HAVING distance < 25 ORDER BY distance;
where [starlat] and [startlng] is the position where to start measuring the distance.
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Concatenate two string literals
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const string message = "Hello" + ",world" + exclam;
The + operator has left-to-right associativity, so the equivalent parenthesized expression is:
const string message = (("Hello" + ",world") + exclam);
As you can see, the two string...
Do any JVM's JIT compilers generate code that uses vectorized floating point instructions?
Let's say the bottleneck of my Java program really is some tight loops to compute a bunch of vector dot products. Yes I've profiled, yes it's the bottleneck, yes it's significant, yes that's just how the algorithm is, yes I've run Proguard to optimize the byte code, etc.
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How is attr_accessible used in Rails 4?
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Rails 4 now uses strong parameters.
Protecting attributes is now done in the controller. This is an example:
class PeopleController < ApplicationController
def create
Person.create(person_params)
end
private
def person_params
para...
Why should I use Restify?
I had the requirement to build up a REST API in node.js and was looking for a more light-weight framework than express.js which probably avoids the unwanted features and would act like a custom-built framework for building REST APIs. Restify from its intro is recommended for the same case.
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How to measure time taken by a function to execute
I need to get execution time in milliseconds.
28 Answers
28
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Get exit code of a background process
... how close it is to finishing. (ps | grep isn't idiot-proof. If you have time you can come up with a more robust way to tell whether the process is still running).
Here's a skeleton script:
# simulate a long process that will have an identifiable exit code
(sleep 15 ; /bin/false) &
my_pid=$!
wh...
Returning a boolean from a Bash function
...hen echo "is directory"; else echo "nopes"; fi
Edit
From @amichair's comment, these are also possible
isdirectory() {
if [ -d "$1" ]
then
true
else
false
fi
}
isdirectory() {
[ -d "$1" ]
}
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Is there a way to iterate over a range of integers?
...ut I was wondering if there is a way to iterate over a range of numbers, something like this:
11 Answers
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How to extract epoch from LocalDate and LocalDateTime?
How do I extract the epoch value to Long from instances of LocalDateTime or LocalDate ? I've tried
the following, but it gives me other results:
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