R: Create a stacked area plot of time series in ggplot2

Question

I have a data frame that is a percentage allocation for each variable. There are four variables where the sum of the rows are equal to 1. Here is a example output of the data frame:

dates       A   B   C   D
1997-01-01  0.2 0.2 0.5 0.1 
1997-02-01  0.3 0.2 0.4 0.1
1997-03-01  0.1 0.3 0.2 0.4
...         ... ... ... ...
2017-12-01  0.2 0.2 0.1 0.5

How can I create a similar stacked area plot like where the x-axis shows the years, and y-axis is from 0 to 1 (from https://ggplot2.tidyverse.org/reference/geom_density.html):

My attempt at following the instructions produced this, which is not exactly what I am looking for:

I get the error message:

Error: A:D must evaluate to column positions or names, not a double vector

In addition: Warning messages:

1: In x:y : numerical expression has 252 elements: only the first used

2: In x:y : numerical expression has 252 elements: only the first used

I used `ggplot(df, aes(x = dates, y = values)) + geom_area(position = "fill")` — Mataunited18, Aug 09 '18 at 13:31
My data frame looks like this `df <- data.frame(dates = dates, value = cbind(A, B, C, D))`. — Mataunited18, Aug 09 '18 at 13:42
Please [see here](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) on making an R post that's easy to answer. That includes a representative sample of your data, code you've written so far, and any error messages we should know about, *posted in the question*. — camille, Aug 09 '18 at 14:17

score 4 · Accepted Answer · answered Aug 09 '18 at 13:11

4

I guess you want area, not density. Also you want to reshape your data to a long format.

library(tidyverse)

df <- read.table(text = "
dates       A   B   C   D
1997-01-01  0.2 0.2 0.5 0.1 
1997-02-01  0.3 0.2 0.4 0.1
1997-03-01  0.1 0.3 0.2 0.4
", header = TRUE)

df %>% 
  mutate(dates = as.Date(dates)) %>% 
  gather(variable, value, A:D) %>% 
  ggplot(aes(x = dates, y = value, fill = variable)) +
  geom_area()

answered Aug 09 '18 at 13:11

Jack Brookes

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I only get error messages when I try your code. My `df` is also a data frame and structured like yours. – Mataunited18 Aug 09 '18 at 13:45
In that case the error is very clear. Your dataframe does not contain the columns `A` to `D`. – Jack Brookes Aug 09 '18 at 14:20
That is weird. Because I have four columns A, B, C and D. And I have also tried to give names through `colnames()`. `dim` also gives 5 in cols. – Mataunited18 Aug 09 '18 at 17:42
I resolved the issue. However, do you know how to add black lines to each variable, i.e. black lines at the edges? – Mataunited18 Aug 12 '18 at 08:37
1

`geom_area(color = "black")` – Jack Brookes Aug 12 '18 at 11:58

R: Create a stacked area plot of time series in ggplot2

1 Answers1