Combine contents in different columns into one column

Question

Dear Stack overflow genius,

I am trying to combine a data.frame containing 10 columns into 1 column and then remove duplicate. Now I am doing it in a stupid way, can anyone show me how to loop it? Sry I am so new to R. Thank you so much!

The data is very simple and here is just an example

C1	c2	c3	c4	c5	c6	c7	c8	c9	c10
13	16	19	1	20	36	8	22	10	20
15	20	16

`col1 <- as.character(allcol[,1])
 col2 <- as.character(allcol[,2])
 col3 <- as.character(allcol[,3])
 col4 <- as.character(allcol[,4])
 col5 <- as.character(allcol[,5])
 col6 <- as.character(allcol[,6])
 col7 <- as.character(allcol[,7])
 col8 <- as.character(allcol[,8])
 col9 <- as.character(allcol[,9])
 col10 <- as.character(allcol[,10])`

allcol <- c(col1,col2,col3,col4,col5,col6,col7,col8,col9,col10) uniqueallcol <- unique(allcol)

Answer 1

If all your columns have the same data type (numeric, for example), you can transform your data frame into a single vector with unlist , remove duplicates in the resulting vector with unique , and then turning it back into a data frame with data.frame :

uniqueallcol <- data.frame("unique_col" = unique(unlist(allcol)))