# A tibble: 6 × 14
name height mass hair_color skin_color eye_color birth_year sex gender
<chr> <int> <dbl> <chr> <chr> <chr> <dbl> <chr> <chr>
1 Luke Sky… 172 77 blond fair blue 19 male mascu…
2 C-3PO 167 75 <NA> gold yellow 112 none mascu…
3 R2-D2 96 32 <NA> white, bl… red 33 none mascu…
4 Darth Va… 202 136 none white yellow 41.9 male mascu…
5 Leia Org… 150 49 brown light brown 19 fema… femin…
6 Owen Lars 178 120 brown, gr… light blue 52 male mascu…
# ℹ 5 more variables: homeworld <chr>, species <chr>, films <list>,
# vehicles <list>, starships <list>
2 Long vs. wide format
tatooine <- starwars %>%filter(homeworld =="Tatooine") # select only those from Tatooine
tibble: is a dataframe specific version for tidyverse. It is both an object and a tibble. So it talks well with all of the related packages. Columns in a tibble are character vectors (instead of factors). This is technically easier to deal with.
Create a table of droids that are equal to or greater than 96 inches in height.
3 Summarizing data
What are the average masses of humans versus ewoks?
Use group_by() and summarize().
starwars %>%filter(species =="Human"| species =="Ewok") %>%group_by(species) %>%summarise(MEAN_mass =mean(mass))# Modify the above to remove NAs and get a values for Humans.
What about the average mass of humans and Ewoks on different planets?
starwars %>%filter(species =="Human"| species =="Ewok") %>%group_by(species, homeworld) %>%summarise(MEAN_mass =mean(mass))
summarize() creates a smaller output table, or a summary. This is dictated by group_by(). Mutate() adds a column to the data.
3.0.1 Activity
Add a column to star wars that classifies tall versus short, based on the height of each species.
Add a column that defines if the species is Human versus non-human.
What are the mean masses of humans versus non-humans? And how many examples are included in this table.
What are the max and min heights of humans and non-humans by planet?
4 Star wars data wrangling
Isolate non-droids on Alderaan, Naboo, Endor, Kamino, and Coruscant. Based on their reported sex, is there a relationship between their heigh, planet, and species?
head(starwars)
# A tibble: 6 × 14
name height mass hair_color skin_color eye_color birth_year sex gender
<chr> <int> <dbl> <chr> <chr> <chr> <dbl> <chr> <chr>
1 Luke Sky… 172 77 blond fair blue 19 male mascu…
2 C-3PO 167 75 <NA> gold yellow 112 none mascu…
3 R2-D2 96 32 <NA> white, bl… red 33 none mascu…
4 Darth Va… 202 136 none white yellow 41.9 male mascu…
5 Leia Org… 150 49 brown light brown 19 fema… femin…
6 Owen Lars 178 120 brown, gr… light blue 52 male mascu…
# ℹ 5 more variables: homeworld <chr>, species <chr>, films <list>,
# vehicles <list>, starships <list>
