I am working with a heat map, as in the REPREX below. The code works
fine as long as "bigger numbers imply greener and smaller numbers imply
redder". These are time series where bigger numbers are "better", like
total employment for example. But I also have cases within the heat map
where "bigger numbers imply redder and smaller numbers imply greener".
These are time series where bigger numbers are "worse", like total
unemployment for example. So suppose column B in dat is of the second
type, i.e. "bigger numbers imply redder and smaller numbers imply
greener". I would like the colour coding to be the reverse of what it is
for columns A and C. How can I modify the code to accomplish this? I
have tried different approaches with no success. Thanks for your help.
Philip
# REPREX
library(ggplot2)
library(tidyr)
library(dplyr)
dat <- data.frame(
date=seq.Date(as.Date("2024-01-01"),as.Date("2024-06-01"),by="month"),
A=c(1,3,3,4,2,6),
B=c(3,5,6,4,8,9),
C=c(10,8,17,19,26,22)
)
dat_long <- pivot_longer(dat,2:4,names_to="variable",values_to="value")
normalize <- function(x) { y <- (x-min(x))/(max(x)-min(x)) }
dat_norm <- mutate(dat,across(2:4,normalize))
dat_long_norm <-
pivot_longer(dat_norm,2:4,names_to="variable",values_to="norm_value")
dat_long <- inner_join(dat_long,dat_long_norm,by=c("date","variable"))
heatmap <- ggplot(dat_long, aes(x = date, y = variable,fill=norm_value))
+
geom_tile() +
geom_text(aes(label = as.character(value)),
color = "black", size = 2.5) +
labs(title="REPREX",x="",y="")+
scale_fill_gradient2(low = "#E94A26", mid = "white", high = "#A1D385",
midpoint = 0.5) +
scale_x_continuous(breaks=seq.Date(as.Date("2024-01-01"),
as.Date("2024-06-01"),by="month"),
labels=function(x) format(x,"%b\n%Y"),position="top")+
theme(legend.position="none")
heatmap
ggsave("REPREXHeatmap.png",heatmap,height=3.5,width=4.9,dpi=200)
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide https://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
