R：宽到长和填充日期

Question

week = seq(as.Date("2022-9-1"), as.Date("2022-10-1"), by="weeks")
visits = c("[1,2,6,4,6,11,19]", "[12,2,7,8,6,11,22]", 
       "[8,2,5,8,4,15,13]", "[9,2,7,4,6,11,7]", 
       "[25,34]")
data = data.frame(week, visits)

The above data frame records daily visit in a string column, and each row represents a week.

I would like to convert the above dataset to a long table with daily visits. This is the expected output:

date	visits
2022-9-1	1
2022-9-2	2
2022-9-3	6
2022-9-3	6
....
2022-9-30	34

I have tried the following steps: (1) break down the string using strsplit and remove the first and last item (which is [ and ] ); (2) store each day's visit in separate columns; (3) use dplyr::mutate and dplyr::complete to fill the dates between weeks; (4) then loop over each first day of the week to make each week's wide data to long data. All these add to 60ish lines of code, where I feel that there might be an easier solution.

Thank you so much in advance!

Answer 1

Perhaps this helps

library(dplyr)
library(tidyr)
library(stringr)
data %>% 
  mutate(visits = str_remove_all(visits, "\\]|\\[")) %>% 
  separate_rows(visits) %>%
  group_by(week) %>% 
  mutate(date = seq(first(week), length.out = n(), 
     by = '1 day'), .before = 'week') %>%
  ungroup %>%
  select(-week)

-output

# A tibble: 30 × 2
   date       visits
   <date>     <chr> 
 1 2022-09-01 1     
 2 2022-09-02 2     
 3 2022-09-03 6     
 4 2022-09-04 4     
 5 2022-09-05 6     
 6 2022-09-06 11    
 7 2022-09-07 19    
 8 2022-09-08 12    
 9 2022-09-09 2     
10 2022-09-10 7     
# … with 20 more rows