Add a prefix to all rows in R

r syntax prefix
user3091668 picture user3091668 · Jun 5, 2014 · Viewed 10.8k times · Source

I am trying to add a prefix end to all rows in a col ensnp in a dataframe chrs:

 Name    endsnp
Bov001   Bov001
Bov002   Bov001

My expected output must be like that:

 Name     endsnp
Bov001   endBov001
Bov002   endBov001

I have tried chrs <- transform(chrs, endsnp = sprintf("end", endsnp)), but I get this output:

 Name     endsnp
Bov001     end
Bov002     end

Any ideas about my error? Thank you!

Answer

csgillespie picture csgillespie · Jun 5, 2014

Just use paste0 to combine strings.

For example, 

chrs$endsnp = paste0('end', chrs$endsnp)

or using paste and specifing the separator between the strings

chrs$endsnp = paste('end', chrs$endsnp, sep='')

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