R: constructing a data frame with many columns using paste()

Question

col1 <- c(1, 2, 3)
col2 <- c(4, 5, 6)
col3 <- c(7, 8, 9)

• On the one hand data.frame(col1, col2, col3)

gives<

Answer 1

If we already have a string that have the objects pasted together, we can use strsplit to split the string and get the values with mget. This will return a list output. Then wrap it with data.frame to convert it to 'data.frame`

data.frame(mget(strsplit(str1, ', ')[[1]])) 

data

str1 <- paste0("col", 1:3, collapse=", ")

Answer 2

You may want to use mget

do.call(cbind, mget(paste0("col", 1:3)))

Where the paste0 generates the variable names, mget gets the associated values, and cbind puts them together into a data frame.