user2641103 user2641103 - 3 months ago 15
R Question

Problems with geom_tile and scale_colour_distiller

I want to create a correlation plot using

geom_tile()
. This is a reproducible chunk of code:

library(ggplot2)

df.m <- structure(list(Trait = structure(c(6L, 5L, 1L, 3L, 2L, 9L, 4L,
10L, 11L, 7L, 8L, 6L, 5L, 1L, 3L, 2L, 9L, 4L, 10L, 11L, 7L, 8L,
6L, 5L, 1L, 3L, 2L, 9L, 4L, 10L, 11L, 7L, 8L), .Label = c("R1",
"R2", "R3", "R4", "R5",
"R6", "R7", "R8",
"R9", "R10",
"R11"), class = "factor"), Variable = structure(c(3L,
3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 2L, 2L, 2L, 2L, 2L, 2L,
2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L
), .Label = c("C1", "C2", "C3"), class = "factor"),
value = c(0.967444360256195, 0.937379062175751, 0.647411823272705,
0.512605130672455, 0.50750744342804, 0.508640229701996, 0.508640229701996,
0.503542542457581, 0.442936152219772, 0.510905921459198,
0.504675328731537, NA, 0.834005177021027, 0.667642116546631,
0.579914391040802, 0.579344689846039, 0.536050498485565,
0.532062888145447, 0.52408766746521, 0.520099997520447, 0.504719197750092,
0.450031787157059, NA, NA, 0.571457028388977, 0.451690584421158,
0.354736804962158, 0.46138596534729, 0.477354824542999, 0.447128057479858,
0.287439465522766, 0.498456537723541, 0.508722245693207)), .Names = c("Trait",
"Variable", "value"), row.names = c(NA, -33L), class = "data.frame")

p <- ggplot(na.omit(df.m)) + aes(x = Variable, y = Trait, fill = value) +
geom_tile(colour = "white", size = 0.75) +
scale_colour_distiller(limits = c(-1, 1), direction = -1, palette = "RdBu", name = "Coefficient") +
scale_size(range = c(0,20), name = title, guide = "none") +
geom_text(data = df.m, aes(x = Variable, y = Trait, label = sprintf("%.2f", value)), size = 4, inherit.aes = FALSE) +

theme(plot.title = element_text(size = 20), axis.text.y = element_text(size = 10),
axis.text.x = element_text(size = 10, angle = 90, hjust = 1, vjust = 0.5),
legend.position = "bottom", legend.margin = unit(1.0, "cm"),
legend.text = element_text(size = 8), legend.title = element_text(size = 10),
legend.key.size = unit(1.0, "cm"),
panel.background = element_rect(fill = "white")) +

xlab("\nVariables 1") + ylab("Variables 2\n")

plot(p)


However, the tiles are filled with their own color gradient scale and not with the one defined bye
scale_colour_distiller()
. Moreover, both key legends appear in the plot:

enter image description here

I just want the tiles to be colored according to the gradient defined by the
scale_colour_distiller()
. How can I do that? From where
geom_plot()
is sucking the color scale?

Thanks in advance!

Answer

You need to use scale_fill_distiller since you are mapping value to the fill aesthetic and not to the color aesthetic.