Rbind dataframes using wildcard

r, rbind, wildcard

Solution

You can do it with `get()` and `ls()`:

'A1-pre' <- matrix(rnorm(100), 5) 
'B3-pos' <- matrix(rnorm(100), 5)
'B4-pre' <- matrix(rnorm(100), 5)
'C5-not' <- matrix(rnorm(100), 5)

names <- grep('pre|pos$', ls(), value=T)

newDF <- mapply(get, grep('pre|pos$', ls(), value=T))

Problem

Suppose I have three dataframes called A1-pre, B3-pos, B4-pre and I want to merge these dataframes. The columns have the same name, so I can use rbind. ``` newdf <- rbind(A1-pre, B3-pos, B4-pre) #this would work ``` However, I do not want to manually input all the names of the dataframes myself, I rather use a wildcard for that, so something like ``` newdf <- rbind(grep(-)) #but this does not work ``` Any idea how I could do that? Or even better, matching any dataframe named "pre" or "pos" and rbind them all.

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