The Lesser-Known Apply Functions In R

Kevin Feasel

2018-11-14

R

Andrew Treadway covers a few of the lesser-known apply functions in R:

rapply

Let’s start with rapply. This function has a couple of different purposes. One is to recursively apply a function to a list. We’ll get to that in a moment. The other use of rapply is to a apply a function to only those elements in a list (or columns in a data frame) that belong to a specified class. For example, let’s say we have a data frame with a mix of categorical and numeric variables, but we want to evaluate a function only on the numeric variables.

Click through for some examples of rapply as well as vapply and eapply.  I’ve used rapply to get cardinality of each feature in a data frame but the other two are new to me.  H/T R-bloggers

Related Posts

Deploying An R Service To Azure Kubernetes Service

Hong Ooi shows us how we can use Azure Container Registry and Azure Kubernetes Service to deploy an R model via Plumber: If you run this code, you should see a lot of output indicating that R is downloading, compiling and installing randomForest, and finally that the image is being pushed to Azure. (You will […]

Read More

Road Construction Incentive Contracts And R

Sebastian Kranz promotes an interesting RTutor project: Patrick Bajari and Gregory Lewis have collected a detailed sample of 466 road construction projects in Minnesota to study this question in their very interesting article Moral Hazard, Incentive Contracts and Risk: Evidence from Procurement in the Review of Economic Studies, 2014.They estimate a structural econometric model and find that […]

Read More

Categories

November 2018
MTWTFSS
« Oct Dec »
 1234
567891011
12131415161718
19202122232425
2627282930