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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...
Random record from MongoDB
I am looking to get a random record from a huge (100 million record) mongodb .
26 Answers
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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 to check BLAS/LAPACK linkage in NumPy and SciPy?
I am builing my numpy/scipy environment based on blas and lapack more or less based on this walk through.
5 Answers
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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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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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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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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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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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SLF4J: Failed to load class “org.slf4j.impl.StaticLoggerBinder”
My application is to be deployed on both tcServer and WebSphere 6.1. This application uses ehCache and so requires slf4j as a dependency.
As a result I've added the slf4j-api.jar (1.6) jar to my war file bundle.
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