Combine two dataframe columns in R -

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this question has answer here:

suppose have dataframe such as:
b c
a
b b
d e

and want create new column in dataframe b , c combined (call d).

a b c d
aa
b b bb
d e ea

you can use paste. 

  df1$d <- do.call(paste0, df1[c('b', 'c')])

or

  df1 <- transform(df1, d= paste0(b,c))

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