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rdataframeggplot2plothistogram

Histograms with different bins grouped

I have this dataset:

Set,SVMLinear,SVMPoly
    x,0.5,0.6
    y,0.9,0.8
    z,0.8,0.7

How can I compute a ggplot in R such that in the x-axis are presented the 3 Sets (x, y, z), and for each set I have 2 bins (one for SVMLinear and the other for SVMPoly) with 2 different colors?

Thanks

Solution

  • Sounds like you're after a bar chart? Here's a solution using ggplot2 and data.table:

    library(ggplot2)
library(data.table)
dt <- data.table(
  Set=c("x","y","z"),
  SVMLinear=c(0.5,0.9,0.8),
  SVMPoly=c(0.6,0.8,0.7)
)
dt <- melt(dt, id.vars="Set")

ggplot(data=dt, aes(x=Set, y=value, fill=variable)) +
  geom_col(position = "dodge") +
  scale_fill_discrete(name="Model:")

    The chart looks like this:

    enter image description here