In a data frame, repeat / complete rows based on multiples months extraction-CodePudding

I have a dataframe :

details <- "I stay in april in Barcelona, after in may in Paris and finally in july in London. april is a cool month. july has very hot temperatures"

df <- as.data.frame(details)

I can extract months words before cities in a new colmun witth mutateand str_extract from tidyverse package:

 library(tidyverse)
 dfmonths<-  df %>%
  mutate(city_months = str_extract(details, "april|may|july(?=\\sin)")

...but only the fist matched month is in my result :

details                                                               city_months
1 I stay in april in Barcelona (...) and finally in july in Paris.... april

I tried :

 library(tidyverse)
  dfmonths<-  df %>%
   mutate(city_months = str_extract_all(details, 
   "april|may|july(?=\\sin)")

but I have only one row :

details                                                               city_months
1 I stay in april in Barcelona (...) and finally in july in Paris.... april, may, july

How can I do that :

details                                                              city_months
1 I stay in april in Barcelona (...) and finally in july in Paris....april
2 I stay in april in Barcelona (...) and finally in july in Paris.... may
3 I stay in april in Barcelona (...) and finally in july in Paris....july

CodePudding user response：

Use str_extract_all, i.e

library(dplyr)
library(stringr)
library(tidyr)

df %>% 
 mutate(new = str_extract_all(details, "april|may|july(?=\\sin)")) %>% 
 unnest() %>%
 distinct()

# A tibble: 3 x 2
  details                                                                                                                                  new  
  <chr>                                                                                                                                    <chr>
1 I stay in april in Barcelona, after in may in Paris and finally in july in London. april is a cool month. july has very hot temperatures april
2 I stay in april in Barcelona, after in may in Paris and finally in july in London. april is a cool month. july has very hot temperatures may  
3 I stay in april in Barcelona, after in may in Paris and finally in july in London. april is a cool month. july has very hot temperatures july