Às 18:10 de 02/08/2023, Nick Wray escreveu:
Hello - I am trying to plot flows in a number of rivers within the same plot, and need to colour the lines differently, using a colour-blind palette.Code beneath works but has colours assigned by the program I have made some simple dummy data: ## code 1 cb8<- c("#000000", "#E69F00", "#56B4E9", "#009E73","#F0E442", "#0072B2", "#D55E00", "#CC79A7") ## this is the colour-blind palette set.seed(020823) df<-as.data.frame(cbind(rep(1980:1991,2),c(10*runif(12),10*runif(12)),c(rep(1,12),rep(2,12)))) colnames(df)<-c("Year","Flow","Stat") df ggplot(df,aes(Year,Flow,group=Stat,colour=Stat))+ coord_cartesian(ylim = c(0, 10)) + geom_line()+ geom_point() ## this works ## BUT: ## code 2 col.2<-cb8[4:5] ggplot(df,aes(Year,Flow,group=Stat,colour=Stat))+ coord_cartesian(ylim = c(0, 10)) + geom_line()+ geom_point()+ scale_color_manual(values =cb8[4:5])+ theme_bw() ## this gives error message Error: Continuous value supplied to discrete scale ## However this example using code from the net does work so I don't understand why my ## second code doesn't work. ## code 3 df.1 <- data.frame(store=c('A', 'A', 'A', 'B', 'B', 'B', 'C', 'C', 'C'), week=c(1, 2, 3, 1, 2, 3, 1, 2, 3), sales=c(9, 12, 15, 7, 9, 14, 10, 16, 19)) ggplot(df.1, aes(x=week, y=sales, group=store, color=store)) + geom_line(size=2) + #scale_color_manual(values=c('orange', 'pink', 'red')) scale_color_manual(values=cb8[4:6]) Can anyone help? Thanks Nick Wray [[alternative HTML version deleted]] ______________________________________________ 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 http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Hello, Your Stat column is numeric, therefore, ggplot sees it as continuous. To make it work, coerce to factor. Here are two ways. ## 1st way, Stat coerce to factor in the ggplot code ## this means you will have to set the legend name ## manually in scale_color_manual ## code 2, now it works col.2<-cb8[4:5] ggplot(df, aes(Year,Flow, group = factor(Stat), colour = factor(Stat)))+ coord_cartesian(ylim = c(0, 10)) + geom_line()+ geom_point()+ scale_color_manual(name = "Stat", values = cb8[4:5])+ theme_bw() ## 2nd way, since you are using ggplot2, a tidyverse package, ## coerce to factor in a pipe before the ggplot call ## this is done with dplyr::mutate and R's native pipe operator ## (could also be magritttr's pipe) ## I have left name = "Stat" like above though it's no ## longer needed df |> dplyr::mutate(Stat = factor(Stat)) |> ggplot(aes(Year, Flow, group = Stat, colour = Stat))+ coord_cartesian(ylim = c(0, 10)) + geom_line()+ geom_point()+ scale_color_manual(name = "Stat", values = cb8[4:5])+ theme_bw() Hope this helps, Rui Barradas ______________________________________________ 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 http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
