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Boolean operators && and ||
According to the R language definition , the difference between & and && (correspondingly | and || ) is that the former is vectorized while the latter is not.
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Why is MATLAB so fast in matrix multiplication?
I am making some benchmarks with CUDA, C++, C#, Java, and using MATLAB for verification and matrix generation. When I perform matrix multiplication with MATLAB, 2048x2048 and even bigger matrices are almost instantly multiplied.
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INNER JOIN vs LEFT JOIN performance in SQL Server
I've created SQL command that uses INNER JOIN on 9 tables, anyway this command takes a very long time (more than five minutes). So my folk suggested me to change INNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got si...
Why is it said that “HTTP is a stateless protocol”?
...ocket. That is solely a performance thing, intended to minimize the time/bandwidth that'd otherwise be spent reestablishing a connection for each request.
As far as HTTP is concerned, they are all still separate requests and must contain enough information on their own to fulfill the request. Tha...
What is the difference between a directory and a folder?
Most people use the terms "folder" and "directory" interchangeably. From a programmer point of view, is there a difference, and if so, what is it? Does it depend on the OS, or is there a broad, general consensus? This at least suggests that there is a difference.
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How do I execute a string containing Python code in Python?
...ting code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, to see if these can better meet your needs.
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How can I use Google's Roboto font on a website?
I want to use Google's Roboto font on my website and I am following this tutorial:
13 Answers
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Twitter Bootstrap 3: how to use media queries?
...ecause "extra small" is the default. I.e. you would first code the XS size and then have these media overrides afterwards.
@media(min-width:576px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}
Update 2019-02-11: BS3 info is still accurate as of version 3.4.0, up...
Why is i++ not atomic?
...crement operation atomic; it involves synchronization at both the software and hardware levels that need not be present in an ordinary increment.
You could make the argument that i++ should have been designed and documented as specifically performing an atomic increment, so that a non-atomic increm...
How to fix corrupted git repository?
...loning my repository which I keep on my Ubuntu one folder to a new machine and I got this:
14 Answers
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