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How to check if variable's type matches Type stored in a variable
How do I test if some variable is of some type in this way?
4 Answers
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Best way to store time (hh:mm) in a database
I want to store times in a database table but only need to store the hours and minutes.
I know I could just use DATETIME and ignore the other components of the date, but what's the best way to do this without storing more info than I actually need?
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Are there any downsides to passing structs by value in C, rather than passing a pointer?
...value: Stack space.
A lot of C programming is for embedded systems, where memory is at a premium, and stack sizes may be measured in KB or even Bytes... If you're passing or returning structs by value, copies of those structs will get placed on the stack, potentially causing the situation that this...
Get an OutputStream into a String
...Charset. A possible value is java.nio.charset.StandardCharsets.UTF_8.
The method toString() accepts only a String as a codepage parameter (stand Java 8).
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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
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