myfun <- function(x) {
if(is.numeric(x)){
ifelse(is.na(x), x, paste0(round(x*100L, 1), "%"))
} else x
}
df1 %>% mutate_each(funs(myfun))
# name somevariable othervariable
# 1 A1 13.4% 53.4%
# 2 A1 54.8% <NA>
# 3 B1 36.9% 36.9%
# 4 B1 <NA> 33.3%