library(tidyverse)Solution to tidyr task
1 Get started
2 Let’s tidy some data sets
1. relig_income
Have a look at the relig_income data set that is included in tidyverse package. The data set contains the results of a survey asking people about their religion and income category.
relig_income# A tibble: 18 × 11
religion `<$10k` `$10-20k` `$20-30k` `$30-40k` `$40-50k` `$50-75k` `$75-100k`
<chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 Agnostic 27 34 60 81 76 137 122
2 Atheist 12 27 37 52 35 70 73
3 Buddhist 27 21 30 34 33 58 62
4 Catholic 418 617 732 670 638 1116 949
5 Don’t k… 15 14 15 11 10 35 21
6 Evangel… 575 869 1064 982 881 1486 949
7 Hindu 1 9 7 9 11 34 47
8 Histori… 228 244 236 238 197 223 131
9 Jehovah… 20 27 24 24 21 30 15
10 Jewish 19 19 25 25 30 95 69
11 Mainlin… 289 495 619 655 651 1107 939
12 Mormon 29 40 48 51 56 112 85
13 Muslim 6 7 9 10 9 23 16
14 Orthodox 13 17 23 32 32 47 38
15 Other C… 9 7 11 13 13 14 18
16 Other F… 20 33 40 46 49 63 46
17 Other W… 5 2 3 4 2 7 3
18 Unaffil… 217 299 374 365 341 528 407
# ℹ 3 more variables: `$100-150k` <dbl>, `>150k` <dbl>,
# `Don't know/refused` <dbl>What is not tidy about this data set?
The variable income is spread across multiple columns, so we have to use pivot_longer to pivot the columns containing the income information:
pivot_longer(relig_income,
cols = !religion,
names_to = "income",
values_to = "count"
)# A tibble: 180 × 3
religion income count
<chr> <chr> <dbl>
1 Agnostic <$10k 27
2 Agnostic $10-20k 34
3 Agnostic $20-30k 60
4 Agnostic $30-40k 81
5 Agnostic $40-50k 76
6 Agnostic $50-75k 137
7 Agnostic $75-100k 122
8 Agnostic $100-150k 109
9 Agnostic >150k 84
10 Agnostic Don't know/refused 96
# ℹ 170 more rows2. billboard
Have a look at the billboard data set that is included in the tidyverse package. The data set contains information about the chart rank of songs in the year 2000.
billboard# A tibble: 317 × 79
artist track date.entered wk1 wk2 wk3 wk4 wk5 wk6 wk7 wk8
<chr> <chr> <date> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 2 Pac Baby… 2000-02-26 87 82 72 77 87 94 99 NA
2 2Ge+her The … 2000-09-02 91 87 92 NA NA NA NA NA
3 3 Doors D… Kryp… 2000-04-08 81 70 68 67 66 57 54 53
4 3 Doors D… Loser 2000-10-21 76 76 72 69 67 65 55 59
5 504 Boyz Wobb… 2000-04-15 57 34 25 17 17 31 36 49
6 98^0 Give… 2000-08-19 51 39 34 26 26 19 2 2
7 A*Teens Danc… 2000-07-08 97 97 96 95 100 NA NA NA
8 Aaliyah I Do… 2000-01-29 84 62 51 41 38 35 35 38
9 Aaliyah Try … 2000-03-18 59 53 38 28 21 18 16 14
10 Adams, Yo… Open… 2000-08-26 76 76 74 69 68 67 61 58
# ℹ 307 more rows
# ℹ 68 more variables: wk9 <dbl>, wk10 <dbl>, wk11 <dbl>, wk12 <dbl>,
# wk13 <dbl>, wk14 <dbl>, wk15 <dbl>, wk16 <dbl>, wk17 <dbl>, wk18 <dbl>,
# wk19 <dbl>, wk20 <dbl>, wk21 <dbl>, wk22 <dbl>, wk23 <dbl>, wk24 <dbl>,
# wk25 <dbl>, wk26 <dbl>, wk27 <dbl>, wk28 <dbl>, wk29 <dbl>, wk30 <dbl>,
# wk31 <dbl>, wk32 <dbl>, wk33 <dbl>, wk34 <dbl>, wk35 <dbl>, wk36 <dbl>,
# wk37 <dbl>, wk38 <dbl>, wk39 <dbl>, wk40 <dbl>, wk41 <dbl>, wk42 <dbl>, …What is not tidy about this data set?
The variable week is spread across multiple columns. We have to use pivot longer to pivot the week columns:
pivot_longer(billboard,
cols = wk1:wk76,
names_to = "week",
values_to = "rank")# A tibble: 24,092 × 5
artist track date.entered week rank
<chr> <chr> <date> <chr> <dbl>
1 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk1 87
2 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk2 82
3 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk3 72
4 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk4 77
5 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk5 87
6 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk6 94
7 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk7 99
8 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk8 NA
9 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk9 NA
10 2 Pac Baby Don't Cry (Keep... 2000-02-26 wk10 NA
# ℹ 24,082 more rows3 Extras
values_drop_na argument
The argument values_drop_na drops rows with missing values in the rank column. Here it makes sense because not every song is in the charts for all 76 weeks.
With the names_prefix argument we can remove the wk before the values of the week variable. This makes it easier to work with later.
pivot_longer(billboard,
cols = wk1:wk76,
names_to = "week",
names_prefix = "wk",
values_to = "rank",
values_drop_na = TRUE)# A tibble: 5,307 × 5
artist track date.entered week rank
<chr> <chr> <date> <chr> <dbl>
1 2 Pac Baby Don't Cry (Keep... 2000-02-26 1 87
2 2 Pac Baby Don't Cry (Keep... 2000-02-26 2 82
3 2 Pac Baby Don't Cry (Keep... 2000-02-26 3 72
4 2 Pac Baby Don't Cry (Keep... 2000-02-26 4 77
5 2 Pac Baby Don't Cry (Keep... 2000-02-26 5 87
6 2 Pac Baby Don't Cry (Keep... 2000-02-26 6 94
7 2 Pac Baby Don't Cry (Keep... 2000-02-26 7 99
8 2Ge+her The Hardest Part Of ... 2000-09-02 1 91
9 2Ge+her The Hardest Part Of ... 2000-09-02 2 87
10 2Ge+her The Hardest Part Of ... 2000-09-02 3 92
# ℹ 5,297 more rowsRecreating the penguin plot
To recreate the penguin plot from the task, the following observations help:
- Information needed: Species, bill depth and bill length
- In a first step, you can therefore use
selectfromdplyrto select only these three columns
- In a first step, you can therefore use
- Aesthetics are: Species on x-axis, value of bill depth and length on y-axis, fill aesthetic is category bill depth or bill length.
- This needs some reformatting. You need one value column with the measurements, and one name column with the category. You can use pivot longer for this
Use the pipe operator to do the calculations one after the other:
library(palmerpenguins)
penguins |>
select(species, bill_length_mm, bill_depth_mm) |>
pivot_longer(!species, names_to = "variable") |>
ggplot(aes(x = species, y = value, fill = variable)) +
geom_boxplot()