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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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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...
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 am I getting this error: No mapping specified for the following EntitySet/AssociationSet - Entit
... state that the SSDL does not exist. You can drag entities, associate them and so forth and yet, if you take a look at the SSDL on the EDMX file, you will see that none of the entities have an associated storage table in the SSDL.
That changes when you click the Generate Database From Model context...
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...
When is assembly faster than C?
...actually be used to generate more performant code are both extremely rare and require expert knowledge of and experience with assembly.
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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...
When should you branch?
...ing out the following article, which explains the principles of branching, and when to use them:
Ned Batchelder - Subversion branching quick start
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