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R - Concatenate two dataframes?
...2 data frames, you can use Reduce(rbind, list_of_data_frames) to mash them all together!
– Yourpalal
Aug 13 '15 at 21:12
1
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Why is it bad practice to call System.gc()?
...ring a 1.5GB HashMap) with System.gc() , I was told it's bad practice to call System.gc() manually, but the comments were not entirely convincing. In addition, no one seemed to dare to upvote, nor downvote my answer.
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C++ performance challenge: integer to std::string conversion
... val /= 10;
}
return s;
}
This will blow up on systems that disallow unaligned memory accesses (in which case, the first unaligned assignment via *(short*) would cause a segfault), but should work very nicely otherwise.
One important thing to do is to minimize the use of std::string. (I...
Make a link in the Android browser start up my app?
...o look at the <intent-filter> element of your Mainfest file. Specifically, take a look at the documentation for the <data> sub-element.
Basically, what you'll need to do is define your own scheme. Something along the lines of:
<intent-filter>
<data android:scheme="anton" /...
Big O of JavaScript arrays
...pending - Amortized O(1) (sometimes resizing the hashtable is required; usually only insertion is required)
Prepending - O(n) via unshift, since it requires reassigning all the indexes
Insertion - Amortized O(1) if the value does not exist. O(n) if you want to shift existing values (Eg, using splice...
What should Xcode 6 gitignore file include?
...ods
Pods
which I believe is the same .gitignore that GitHub sets up with all their repositories by default.
2)
Another answer is that there's a website called "gitignore.io" , which generates the files based on the .gitignore templates from https://github.com/github/gitignore.
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Redirect stderr and stdout in Bash
...
@Daniel, but this question is specifically about bash
– John La Rooy
Aug 19 '13 at 3:38
3
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Why was the switch statement designed to need a break?
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Many answers seem to focus on the ability to fall through as the reason for requiring the break statement.
I believe it was simply a mistake, due largely because when C was designed there was not nearly as much experience with how these constructs would be used.
Peter ...
Difference between ActionBarSherlock and ActionBar Compatibility
...t a native one.
--EDIT--
It appears things have changed and there is actually no difference between ActionBarSherlock and the Action Bar Compatibility anymore. Please read the comments below for details.
--EDIT--
After having used both now, I can say that I actually prefer ActionBarSherlock to A...
Big-oh vs big-theta [duplicate]
It seems to me like when people talk about algorithm complexity informally, they talk about big-oh. But in formal situations, I often see big-theta with the occasional big-oh thrown in.
I know mathematically what the difference is between the two, but in English, in what situation would using big-oh...