create columns according to row values, loop r-CodePudding

I have a data frame like this one:

ID  CODE
 1  code_12
 1  code_67
 2  code_76
 3  code_34

I would like to put each "CODE" I have on my rows in a column by assigning a 1 for the subjects that have this code in row and 0 otherwise.

When the same subject has several lines (for example subject 1), I would like to repeat the "1" on all its lines, in order to obtain a df like this one:

ID  CODE      code_12   code_67  code_76  code_34
 1  code_12   1         1        0        0
 1  code_67   1         1        0        0
 2  code_76   0         0        1        0
 3  code_34   0         0        0        1

I managed to do it "code by code" in the way below, but I would like a way to automate this (with a loop or something) if possible as I have a lot of different codes

 df$code_12<-ifelse(df$CODE=="12", "1", "0")

 df<-df%>%
  group_by(ID) %>%  mutate(code_12 = max(code_12))



 df$code_67<-ifelse(df$CODE== "67", "1", "0")

 df<-df%>%
   group_by(ID) %>%  mutate(code_67 = max(code_67))

Thanks in advance for the help

CodePudding user response：

Using tidyr, you can use pivot_wider with a value column set to 1

library(tidyr)

df <- df %>%
  mutate(value = 1) %>%
  pivot_wider(names_from = CODE) %>%
  mutate(across(everything(), ~replace(., is.na(.), 0) )) %>% 
  right_join(df, by = "ID") %>% 
  relocate(CODE, .after = ID)

Output

> df
# A tibble: 4 x 6
     ID CODE    code_12 code_67 code_76 code_34
  <dbl> <chr>     <dbl>   <dbl>   <dbl>   <dbl>
1     1 code_12       1       1       0       0
2     1 code_67       1       1       0       0
3     2 code_76       0       0       1       0
4     3 code_34       0       0       0       1

CodePudding user response：

Here is a base R option using table crossprod

> with(df, cbind(df, crossprod(table(df))[CODE, CODE]))
        ID    CODE code_12 code_67 code_76 code_34
code_12  1 code_12       1       1       0       0
code_67  1 code_67       1       1       0       0
code_76  2 code_76       0       0       1       0
code_34  3 code_34       0       0       0       1