split data frame and create stacked percent barplot in R

Question

My data frame looks like this:

plant  distance
one      1
one      3
one      2
one      3
one      7
one      4
one      6
one      8
one      9
two      1
two      6
two      4
two      8
two      5
two      3
three ……

I want to split distance of each level into groups by interval(for instance,interval=3).

plant  distance group
  one      1    1
  one      3    1
  one      2    1
  one      3    1
  one      7    3
  one      4    2
  one      6    2
  one      8    3
  one      9    3
  two      1    1
  two      6    2
  two      4    2
  two      8    3
  two      5    2
  two      3    1
  three ……

And compute percentage of each group

plant group percentage
one     1     0.44
one     2     0.22
one     3     0.33
two     1     0.33
two     2     0.50
two     3     0.17
three ……

Finally, plot the percentages of each level of each group similar like this: enter image description here

and I do not know how to split each level by interval. Sorry for my English! Thank you for your help!

What exactly do you want? What have you tried? For example, you could split your data frame by using split(my_data$distance, my_data$plant), you could group it by cut(my_data$distance, breaks = seq(min(my_data$distance), max(my_data$distance), 3)) etc. — lukeA
@lukeA Thank you for your reply, I have tried many times and I have updated the post. — just_rookie

lukeA lukeA · Accepted Answer · 2015-03-24T09:10:28

Here's one way to do it using dplyr:

library(dplyr)
library(ggplot2)
my_data %>%
  mutate(group = factor(cut(distance, seq(0, max(distance), 3), F))) %>%
  group_by(plant, group) %>%
  summarise(percentage = n()) %>%
  mutate(percentage = percentage / sum(percentage)) %>%
  ggplot(aes(x = plant, y = percentage, fill = group)) + 
  geom_bar(stat = "identity", position = "stack")

enter image description here

split data frame and create stacked percent barplot in R

1 Answers