Create data frame from list

Question

I have a data frame (mydata) with >200 variables. I would like to automatically subset some of them into a smaller data frame.

The name of the variables I would like to subset follow a naming convention, e.g., "Q1Pct", "Q2Pct", ... "Q18Pct".

I can get a list of the variables using:

Q.names <- setNames(as.list(1:18),paste(paste0("mydata$Q",1:18,"Pct")))

I have tried to combine the list into a new data frame, but it isn't working:

df.QList <- data.frame(Q.names)

I'm sure there is a much better way to do this - please help.

langtang · Accepted Answer · 2022-03-30 23:39:18Z

2

You can try this:

library(dplyr)

select(mydata, all_of(paste0("Q",1:18,"Pct")))

Or, more simply (base R):

mydata[,paste0("Q",1:18,"Pct")]

answered Mar 30, 2022 at 23:39

langtang

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1 Comment

Thank you so much langtang - you're a legend! That works perfectly!