CODEWITHSUNDEEP
rproportions
kate hodson
kate hodson

Reputation: 11

Beginner to R using table of counts to create table of proportions

penguins.table = table

penguins.table( penguins$species, penguins$island )

this created my table of counts.

Next task for to create a table of proportions

penguins.prop= prop.table
penguins.prop = prop.table( penguins.table, 2)

or I've tried this

penguins.prop (penguins.table, 2)

I receive this in R:

Error in marginSums( x, margin) : 'x' is not an array

I'm learning basic r code, but is there something wrong with my code as to why it's not working in particular?

I need to be able to produce a stacked bar plot with the data, however, am stuck trying to achieve this.

Upvotes: 1

Views: 1059

Answers (2)

Shawn Hemelstrand
Shawn Hemelstrand

Reputation: 3228

For proportion of nominal data:

Here is an alternative that just uses base R commands. This way only requires one string of code after you've loaded your data:

#### Load data ####    

penguins <- structure(list(species = c("Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie"), 
                         island = c("Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe"), 
                         sex = c("male", "female", "female", "female", "male", "female", "male", "female", "male", "male"), 
                         body_mass_g = c(3750, 3800, 3250, 3450, 3650, 3625, 4675, 3200, 3800, 4400)), row.names = c(NA, -10L ), class = c("tbl_df", "tbl", "data.frame")) 
    

#### Make proportion table ####
    
prop.table(table(penguins$species,
          penguins$island))

Which gives you the same output as the tidyverse method:

         Biscoe
  Adelie      1

For proportion of numeric data:

If for some reason I am not understanding your query, here is what you can get for proportions if you mean the numeric variable here, body mass, and the only grouping variable of interest, sex:

library(tidyverse)
library(gt)
gt(penguins)

penguins %>% 
  group_by(sex) %>% 
  summarize(Proportion_Mass = body_mass_g/sum(body_mass_g))

This gives you this proportion of mass table:

# A tibble: 10 x 2
# Groups:   sex [2]
   sex    Proportion_Mass
   <chr>            <dbl>
 1 female           0.219
 2 female           0.188
 3 female           0.199
 4 female           0.209
 5 female           0.185
 6 male             0.185
 7 male             0.180
 8 male             0.231
 9 male             0.187
10 male             0.217

Upvotes: 0

jrcalabrese
jrcalabrese

Reputation: 2321

From your first two pieces of code, I'm assuming that you wanted to make a prop.table using species and island. The code below will do that. You can add more variables you're interested in on the select( line next to species and island (or you could just do the whole dataframe with df, but it will be a lot).

df <- structure(list(species = c("Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie", "Adelie"), 
island = c("Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe", "Biscoe"), 
sex = c("male", "female", "female", "female", "male", "female", "male", "female", "male", "male"), 
body_mass_g = c(3750, 3800, 3250, 3450, 3650, 3625, 4675, 3200, 3800, 4400)), row.names = c(NA, -10L ), class = c("tbl_df", "tbl", "data.frame")) 

library(tidyverse)
smalldf <- df %>% select(species, island)
prop.table(x = table(smalldf), margin = 2)
#>         island
#> species  Biscoe
#>   Adelie      1
#prop.table(x = table(df), margin = 2) 
# ^ a lot of output

Upvotes: 1

Related Questions