CODEWITHSUNDEEP
r
PsyR
PsyR

Reputation: 21

R: Writing data frame to text using grouping

I got stuck while trying to get my data into the correct output format. The original data consists of a table with two columns: (1) groupname (2) mailadress, e.g.

groupname   mailadress
group1      [email protected]
group1      [email protected]
group2      [email protected]
group2      [email protected]

But I need the data in the following format and saved as a text file:

# group1
[email protected]
dummy2@hotmail

# group2
[email protected]
[email protected]

I know there must be a way to achieve this using dplyr, e.g. group_walk(), but I've currently run out of ideas... Can anybody give me a hint?

Upvotes: 1

Views: 87

Answers (3)

fils capo
fils capo

Reputation: 316

not sure if i got what you want

x<-df%>%filter(groupname =="group1")%>%select(mailadress)

names(x)<-"group1"
write.table(x, file = "X.txt", sep = "\t",
            row.names = FALSE)

but this wil output

"group1"
"[email protected]"
"[email protected]"

if its not the point tell me better so i can help

Upvotes: 0

PsyR
PsyR

Reputation: 21

Okay, so I found one possible solution. Say the data.frameis df:

export <- df %>% select(groupname, mailadress) %>% group_by(groupname) %>% 
  +     mutate(mails = paste0(mailadress, collapse = "\n")) %>% slice(1) %>% select(groupname, mails)
export$groupname<- paste0("# ",export$groupname)
write.table(export, "export.txt", sep = "\n", row.names = F, col.names = F, quote = F)

Upvotes: 1

Jakub.Novotny
Jakub.Novotny

Reputation: 3047

library(tidyverse)

df <- tribble(
  ~groupname, ~mailadress,
  "group1", "[email protected]",
  "group1", "[email protected]",
  "group2", "[email protected]",
  "group2", "[email protected]"
)


df %>%
  split(df$groupname) %>%
  map(
    ~paste0("# ", .x$groupname[1], "\n", paste(.x$mailadress, collapse = "\n"))
      ) %>%
  unlist() %>%
  paste(collapse = "\n\n") %>%
  cat(file = "output.txt")

Upvotes: 0

Related Questions