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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
Understanding ibeacon distancing
...estimates.
While the distance estimates are useful, they are not perfect, and require that you control for other variables. Be sure you read up on the complexities and limitations before misusing this.
When we were building the Android iBeacon library, we had to come up with our own independent a...
How do I safely pass objects, especially STL objects, to and from a DLL?
How do I pass class objects, especially STL objects, to and from a C++ DLL?
4 Answers
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git rebase, keeping track of 'local' and 'remote'
...se, I often have difficulty working out what is happening with the 'local' and 'remote' when resolving conflicts. I sometimes have the impression that they swap sides from one commit to the next.
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What is the difference between '@' and '=' in directive scope in AngularJS?
I've read the AngularJS documentation on the topic carefully, and then fiddled around with a directive. Here's the fiddle .
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eval command in Bash and its typical uses
After reading the bash man pages and with respect to this post .
10 Answers
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What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier.
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Difference between >>> and >>
What is the difference between >>> and >> operators in Java?
7 Answers
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How to remove a key from Hash and get the remaining hash in Ruby/Rails?
... your five-minutes-of-editing are up, you can always copy, delete, modify, and repost a comment.
– iconoclast
May 13 at 23:17
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Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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