Color in ggplot- continuous value applied to discrete variable

Question

I already saw another question regarding this topic, but I still am not able to change my colors on my grouped barplot in ggplot. It is providing me with a scale of blue, but I want a scale of green. I am veryyy new to ggplot and probably am missing something obvious.

Here is some of my code:

TCplot=ggplot(mTCdf,aes(x=types4,y=TCs,group=years3,color=years3))
+geom_bar(aes(fill=years3),stat="identity",position="dodge",color="black")


mTCdf$types4=factor(mTCdf$types4,levels=c("Single Year Lease","Multi-Year  Lease","Permanent"))
levels(mTCdf$types4)  ###just to get my labels in my desired order

TCplot=TCplot+ggtitle("Total Costs by Transaction_Type")
+theme(plot.title=element_text(lineheight=.7,face="bold"))
+xlab("Transaction Type")
+ylab("Costs ($)")

library(scales)
TCplot=TCplot+scale_y_continuous(labels=comma)        
   TCplot=TCplot+scale_fill_manual(values=c("#66FF22","#33FF22","#33EE22","#33DD22","#33CC22","#33BB22","#33AA22","#339922","#338822","#337722","#336622"))
TCplot=TCplot+scale_fill_manual(values=c("#66FF22","#33FF22","#33EE22","#33DD22","#33CC22","#33BB22","#33AA22","#339922","#338822","#337722","#336622"))

Error: Continuous value supplied to discrete scale!!! argh!

***Can someone please help me apply a green gradient to this?? Thanks!!

Welcome to SO. Thank you for posting your code, but note that we can't actually reproduce it since we don't know what the mTCdf data frame contains. The best way to deal with this problem is to recreate your problem with a minimal example. Alternately you could use dput to output your actual data frame, and paste the results into your question. See here: stackoverflow.com/questions/5963269/… — Drew Steen
Can you please provide a workable example? It's hard to help when I can't reproduce your results. — emhart

Drew Steen Drew Steen · Accepted Answer · 2013-08-19T20:57:00

The problem is that you are treating your years3 column as if it is a discrete (categorical) variable, when R thinks it is continuous (numeric). @JPC's solution fixes your problem, but I suggest that you would do better to fix the underlying problem. This can be done by changing your years3 column to a factor:

mTCdf$years3 <- as.factor(mTCdf$years3)

and then making the plot as you have done.

Color in ggplot- continuous value applied to discrete variable

2 Answers