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Efficient way to return a std::vector in c++
How much data is copied, when returning a std::vector in a function and how big an optimization will it be to place the std::vector in free-store (on the heap) and return a pointer instead i.e. is:
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What is the ideal data type to use when storing latitude / longitude in a MySQL database?
... MYSQL Spatial is a good option, but still has significant limits and caveats (as of 6). Please see my answer below...
– James Schek
Oct 2 '08 at 15:43
1
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MYSQL OR vs IN performance
... not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, ...
Java 8: performance of Streams vs Collections
... the middle of the list using iterator.
Stop writing benchmarking code by hand, use JMH.
Proper benchmarks:
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@BenchmarkMode(Mode.AverageTime)
@OperationsPerInvocation(StreamVsVanilla.N)
public class StreamVsVanilla {
public static final int N = 10000;
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How to update a record using sequelize for node?
I'm creating a RESTful API with NodeJS, express, express-resource, and Sequelize that is used to manage datasets stored in a MySQL database.
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Visual Studio debugging/loading very slow
...") my ASP.NET MVC sites. Not always: at first, the projects will load nice and fast, but once they load slow, they'll always load slow after that. I could be waiting 1-2 minutes or more.
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Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
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The explanation comes from Agner Fog in Optimizing software in C++ and it reduces to how data is accessed and stored in the cache.
For terms and detailed info, see the wiki entry on caching, I'm gonna narrow it down here.
A cache is organized in sets and lines. At a time, only one set is u...
When should the xlsm or xlsb formats be used?
... (in particular, .xlsx , .xlsm , .xlsb ). I've got no problem to understand the use and purpose of .xlsx format but I am still wondering whether we should use a .xlsm or a .xlsb format when creating a file containing some VBA.
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Pass arguments to Constructor in VBA
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Here's a little trick I'm using lately and brings good results. I would like to share with those who have to fight often with VBA.
1.- Implement a public initiation subroutine in each of your custom classes. I call it InitiateProperties throughout all my classes....
How to save and restore multiple different sessions in Vim?
...like
:mksession ~/mysession.vim
Then later you can source that vim file and you'll have your old session back:
:source ~/mysession.vim
or open vim with the -S option:
$ vim -S ~/mysession.vim
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