R: Combine row contents by same pattern

Question

I have a big data frame.

I want to combine row content which with same type pattern, and use "/" symbol separate contents.

For example:

df>
   type  function
    A    cleaning
    A    improve chemical reaction
    A    reduce scratch
    B    improve planarization
    B    improve slurry distribution
    C    cleaning
    C    improve slurry distribution
    D    reduce scratch

I want df transfer to:

df_transfer>

      type  function
       A    cleaning/improve chemical reaction/reduce scratch 
       B    improve planarization/improve slurry distribution
       C    cleaning/improve slurry distribution
       D    reduce scratch

can you please post result of `dput(df)` – Andre Elrico Nov 20 '17 at 07:57 — Andre Elrico, Nov 20 '17 at 07:57

score 4 · Accepted Answer · answered Nov 20 '17 at 08:12

This example should help:

df = data.frame(type = c("A","A","A","B","B"),
                fun = c("cleaning", "improve chemical reaction", "reduce scratch",
                        "improve planarization", "improve slurry distribution"),
                stringsAsFactors = F)

library(dplyr)

df %>%
  group_by(type) %>%
  summarise(fun = paste0(fun, collapse = "/"))

# # A tibble: 2 x 2
#    type                                               fun
#   <chr>                                             <chr>
# 1     A cleaning/improve chemical reaction/reduce scratch
# 2     B improve planarization/improve slurry distribution

I'd suggest you change your column name to something different than function to avoid any unnecessary conflicts with the function command.

Thanks for your answer and suggestion. It's really helpful for me. — Eva, Nov 21 '17 at 02:23

score 0 · Answer 2 · answered Nov 20 '17 at 08:13

x <- c("A","A","A","B","B","C","C","D")
y <- c("cleaning","improve chemical reaction"," reduce scratch"," improve planarization","improve slurry distribution"," cleaning"," improve slurry distribution","reduce scratch")
df <- data.frame(x,y)

this should do the trick:

    df %>% dplyr::select(x, y) %>% 
dplyr::group_by(x) %>%  
dplyr::summarise(y=y %>% 
paste(collapse = " / ")) -> df_transfer

R: Combine row contents by same pattern

2 Answers2