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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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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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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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What is the difference between active and passive FTP?
Can someone tell me what is the difference between active and passive FTP?
Which one is preferable?
5 Answers
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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 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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Function pointers, Closures, and Lambda
I am just now learning about function pointers and, as I was reading the K&R chapter on the subject, the first thing that hit me was, "Hey, this is kinda like a closure." I knew this assumption is fundamentally wrong somehow and after a search online I didn't find really any analysis of this compari...
Find nearest latitude/longitude with an SQL query
I have latitude and longitude and I want to pull the record from the database, which has nearest latitude and longitude by the distance, if that distance gets longer than specified one, then don't retrieve it.
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GCC compile error with >2 GB of code
...+
1/10.*s.x14*s.x15*csc[49302] - 3/5.*s.x14*s.x15*csc[49303] -...
and
double csc19295 = + s.ds0*s.ds1*s.ds2 * ( -
32*s.x12pow2*s.x15*s.x34*s.mbpow2*s.mWpowinv2 -
32*s.x12pow2*s.x15*s.x35*s.mbpow2*s.mWpowinv2 -
32*s.x12pow2*s.x15*s.x35*s.x45*s.mWpowinv2 -...
rig...