How to mutate columns and transform a 8 column dataframe in R to 3 columns-CodePudding

I was solving a question and got stuck at this point : The question is: First, select the business_id and the seven columns that contain the duration information. Then, transform it from a wide data frame (with 8 columns) to a long data frame (with 3 columns). The 3 columns should be (1) business_id, (2) wday, specifying the day of the week, and (3) duration, specifying the duration of open time for a business on a specific weekday.

This is what I got so far I want to mutate the columns in a way I have a column that shows the week day and a column for the opening duration of that day.

CodePudding user response：

Welcome to StackOverflow!

I'll try to answer your questions while also showing you how to write more effective questions that will encourage people to answer. The key is reproducibility, as @Sotos commented. Also, it helps to create a minimal working example that removes a lot of unnecessary data in order to clarify the process.

This code creates a small dataframe similar to what you're starting with.

library(tidyr)

df_wide <- tibble(id = 1:3,
                  mon = rnorm(3),
                  tue = rnorm(3),
                  wed = rnorm(3),
                  thr = rnorm(3))
df_wide
#> # A tibble: 3 × 5
#>      id    mon    tue    wed    thr
#>   <int>  <dbl>  <dbl>  <dbl>  <dbl>
#> 1     1 -0.779 -0.691  1.22  -0.354
#> 2     2  1.16   0.650  0.824 -0.569
#> 3     3  0.128 -1.79  -1.31  -1.33

^{Created on 2023-02-01 by the reprex package (v2.0.1)}

In order to convert your dataframe to long form, you can use the function pivot_longer from the package tidyr. You can find more detailed help on using that function by entering ?pivot_longer. Here it is in action.

library(tidyr)

df_wide <- tibble(id = 1:3,
                  mon = rnorm(3),
                  tue = rnorm(3),
                  wed = rnorm(3),
                  thr = rnorm(3))
df_wide
#> # A tibble: 3 × 5
#>      id    mon    tue    wed    thr
#>   <int>  <dbl>  <dbl>  <dbl>  <dbl>
#> 1     1 -0.864  1.18   0.605 -0.337
#> 2     2 -0.261  0.224 -1.16  -0.359
#> 3     3 -1.28  -0.849  0.333  0.896
df_long <- pivot_longer(data = df_wide,
                        cols = 2:5,
                        names_to = "wday",
                        values_to = "duration")
df_long
#> # A tibble: 12 × 3
#>       id wday  duration
#>    <int> <chr>    <dbl>
#>  1     1 mon     -0.864
#>  2     1 tue      1.18 
#>  3     1 wed      0.605
#>  4     1 thr     -0.337
#>  5     2 mon     -0.261
#>  6     2 tue      0.224
#>  7     2 wed     -1.16 
#>  8     2 thr     -0.359
#>  9     3 mon     -1.28 
#> 10     3 tue     -0.849
#> 11     3 wed      0.333
#> 12     3 thr      0.896

^{Created on 2023-02-01 by the reprex package (v2.0.1)}