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rggplot2geom-bar

Stacked bar plot based in 4 variables with ggplot2

I have a data frame like this:

nthreads ab_1 ab_2 ab_3 ab_4 ...
1        0    0    0    0    ...
2        1    0    12   1    ...
4        2    1    22   1    ...
8        10   2    103  8    ...

Each ab_X represents different causes that trigger an abort in my code. I want to summarize all abort causes in a barplot displaying nthreads vs aborts with different ab_X stacked in each bar.

I can do 

ggplot(data, aes(x=factor(nthreads), y=ab_1+ab_2+ab_3+ab_4)) +
  geom_bar(stat="identity")

But it only gives the total number of aborts. I know there is a fill aes, but I can not make it work with continuous variables.

Solution

  • You have to melt the data frame first 

    library(data.table)
dt_melt <- melt(data, id.vars = 'nthreads')
ggplot(dt_melt, aes(x = nthreads, y = value, fill = variable)) + 
    geom_bar(stat = 'identity')