Convert a dataframe to a vector (by rows)

Question

I have a dataframe with numeric entries like this one

test <- data.frame(x = c(26, 21, 20), y = c(34, 29, 28)) 

How can I get the following vector?

> 26, 34, 21, 29, 20, 28 

I was able to get it using the following, but I guess there should be a much more elegant way

X <- test[1, ] for (i in 2:dim(test)[ 1 ]){    X <- cbind(X, test[i, ])    }  

Answer 1

You can try as.vector(t(test)). Please note that, if you want to do it by columns you should use unlist(test).

Answer 2

c(df$x, df$y) # returns: 26 21 20 34 29 28 

if the particular order is important then:

M = as.matrix(df) c(m[1,], c[2,], c[3,]) # returns 26 34 21 29 20 28  

Or more generally:

m = as.matrix(df) q = c() for (i in seq(1:nrow(m))){   q = c(q, m[i,]) }  # returns 26 34 21 29 20 28