Histogram Subplots Independently Adjust Bin Size

[astrieanna]

This code plots the iris dataset. Each subplot is a histogram; rows are species, columns are measures. The problem is that some histograms have very skinny lines and some have very thick ones; I would expect them to all look about the same with respect to width-of-bars.

using Gadfly, RDatasets
iris = dataset("datasets","iris")
iris2 = melt(iris,:Species)
set_default_plot_size(9inch, 6inch)
plot(iris2,xgroup=:variable,ygroup=:Species,x=:value,Geom.subplot_grid(Geom.histogram))

[dcjones]

I think now that choosing different bin counts for subplots isn't bad, just in this example it does a terrible job. I've made some improvements that should yield better results.

Can you remind me what the other histogram issue you ran into was?

[astrieanna]

When you add color to Geom.bar inside a Geom.subplot_grid, the heights of the bars are all the same.

using Gadfly, RDatasets
iris = dataset("datasets","iris")
iris2 = melt(iris,:Species)

# Happy blue plot
plot(iris2,xgroup=:variable,x=:Species,y=:value,Geom.subplot_grid(Geom.bar))

# Colorful plot
plot(iris2,xgroup=:variable,x=:Species,y=:value,color=:Species,Geom.subplot_grid(Geom.bar))