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Why were pandas merges in python faster than data.table merges in R in 2012?
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It looks like Wes may have discovered a known issue in data.table when the number of unique strings (levels) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (t...
Bomb dropping algorithm
...e to prove we can be greedy in reducing the outer
perimeter.
But, we do know we can be greedy. Because no bomb in layer 2 can ever be more
efficient in reducing layer 2 to 0 than a strategically placed bomb in layer 3. And
for the same reason as before - there is always a bomb we can place in ...
How do I configure Notepad++ to use spaces instead of tabs?
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Ah Language, now that makes sense.
– deed02392
Dec 5 '13 at 16:05
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Remove spaces from std::string in C++
...ithm remove_if and isspace:
remove_if(str.begin(), str.end(), isspace);
Now the algorithm itself can't change the container(only modify the values), so it actually shuffles the values around and returns a pointer to where the end now should be. So we have to call string::erase to actually modify ...
Rails 3 - can't install pg gem
...pplications/Postgres.app/Contents/MacOS/bin:$PATH"
gem install pg should now work. (This is what worked for me.)
Note New versions path looks like:
/Applications/Postgres.app/Contents/Versions/<version>/bin
share
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What are detached, persistent and transient objects in hibernate?
...ng it with a Session:
Long id = (Long) session.save(person);
// person is now in a persistent state
Now, if we close the Hibernate Session, the persistent instance will become a detached instance: it isn't attached to a Session anymore (but can still be modified and reattached to a new Session la...
Connection pooling options with JDBC: DBCP vs C3P0
...a shelf, the Apache Commons folk have taken DBCP out of dormancy and it is now, once again, an actively developed project. Thus my original post may be out of date.
That being said, I haven't yet experienced this new upgraded library's performance, nor heard of it being de-facto in any recent app ...
Why are only final variables accessible in anonymous class?
...r Java 7, keep in mind that with Java 8, closures have been introduced and now it is indeed possible to access a non-final field of a class from its inner class.
– Mathias Bader
Oct 24 '14 at 14:41
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URLs: Dash vs. Underscore [closed]
...le Webmasters: youtube.com/watch?v=AQcSFsQyct8. Per that video (admittedly now 6 years old and possibly not representing the contemporary status quo), foo_bar is treated as a single word while foo-bar is treated as two words - precisely the opposite of what this answer speculates is the case.
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When to use self over $this?
...I did get some more information that I found helpful further down, but for now I was just trying to figure out why I hit my class attributes with $this->attrib and the class constants with self::constant. This helped me understand that better
– MydKnight
Jul...