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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros? [dupli
...oach would be to check how many digits are output by Integer.toHexString() and add a leading zero to each byte if needed. Something like this:
public static String toHexString(byte[] bytes) {
StringBuilder hexString = new StringBuilder();
for (int i = 0; i < bytes.length; i++) {
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rsync: difference between --size-only and --ignore-times
I'm trying to understand what the difference is between two options
4 Answers
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Which version of the git file will be finally used: LOCAL, BASE or REMOTE?
...merge , I open a mergetool called Meld . It opens three files LOCAL, BASE and REMOTE. As I've read LOCAL is my local branch, BASE is common ancestor and REMOTE is the branch to be merged.
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WordPress is giving me 404 page not found for all pages except the homepage
All of a sudden I go to my WordPress website and all the pages give me a 404 page not found page. I'm assuming the problem lies with the permalink structure, which I could swear I did not touch. The permalink setting is on "month and name."
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How to sort a list/tuple of lists/tuples by the element at a given index?
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@Stephen using itemgetter is faster and simpler: key=itemgetter(1) and at the beginning of the file: from operator import itemgetter
– Joschua
Mar 13 '13 at 20:08
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How do I use a Boolean in Python?
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Actually Python didn't have a boolean type for a long time (as in old C), and some programmers still use integers instead of booleans.
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Use rvmrc or ruby-version file to set a project gemset with RVM?
I use RVM, the Ruby Version Manager to specify a Ruby version and a set of gems for each of my Rails projects.
5 Answers
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Cocoa Touch: How To Change UIView's Border Color And Thickness?
... change the background color, but I'd like to also change the border color and thickness, is this possible?
14 Answers
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Transitioning from Windows Forms to WPF
...e now, I have been stuck with Windows Forms development (started with VB6, and has continued through to C# .NET 4.5), and I have pretty much hit the limit of what Windows Forms can do, both using pure .NET, and special effects with Native Code.
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