r - Order of factor levels in facet_wrap

Question

I'd like to produce a facet_wrap where the order of factors within facets is based on the one of the column factor order. The heart of the problem is each group has duplicated factor levels and when I do plotting only one factor level is ordered correctly in the facet_wrap. (See the graph below)

I try to order factor levels in each group and each factor level should be ordered correctly inside of each facet.

Here is my attempt

df_pattern<- data.frame(address = rep(rep(LETTERS[1:3]),3)) 

df_TP <- data.frame(No=rep(seq(1:3)),
                    clas=c("Good","Bad","Ugly"),stringsAsFactors = F)

set.seed(12)
df_ex <- df_pattern%>%
  mutate(No=rep(seq(1:3),each=3))%>%
  left_join(df_TP)%>%
  mutate(clas=sample(clas))%>%
  group_by(No)

#      address    No  clas
#       <fctr> <int> <chr>
#    1       A     1  Good
#    2       B     1  Ugly
#    3       C     1  Ugly
#    4       A     2  Good
#    5       B     2  Ugly
#    6       C     2   Bad
#    7       A     3   Bad
#    8       B     3   Bad
#    9       C     3  Good

Now lets try to sort address levels according to user defined clas column order

set.seed(12)
df_ex <- df_pattern%>%
  mutate(No=rep(seq(1:3),each=3))%>%
  left_join(df_TP)%>%
  mutate(clas=sample(clas))%>%
  group_by(No)%>%
  mutate(clas=factor(clas,levels=c("Good","Bad","Ugly")))%>%
  mutate(address=factor(address,levels=unique(address[order(clas)])))%>%
  mutate(address=as.character(address))%>%
  arrange(No,clas) 

      address    No  clas
#       <fctr> <int> <ord>
#    1       A     1  Good
#    2       B     1  Ugly
#    3       C     1  Ugly
#    4       A     2  Good
#    5       C     2   Bad
#    6       B     2  Ugly
#    7       C     3  Good
#    8       A     3   Bad
#    9       B     3   Bad

As you can see only the No=1 group ordered correctly in the plot. Maybe this because only one factor level in the data set.

> levels(df_ex$address)
[1] "A" "B" "C"

How can we order factor levels in each group and show them in the facet_wrap? according to clas levels in each facet_wrap?

Thanks!

ggplot code

ggplot(df_ex, aes(x=address,y="",fill=clas)) + #x axis bias voltage dependence
  geom_tile() + 
  scale_fill_manual(values=c('Good'="green","Bad"="Blue","Ugly"="black"))+
  facet_wrap(~No,ncol=1,scales = "free_x")+
  theme(legend.position = "top",axis.text.y = element_text(size = 20,angle = 90),axis.text.x = element_text(size=12,face="bold",colour = "black"),
        axis.title.y = element_text(face="bold",size = 20, colour = "black"),
        axis.title.x = element_text(face="bold",size = 20 , colour = "black"),
        strip.text = element_text(size=26, face="bold"),
        strip.background = element_rect(fill="#FFFF66", colour="black", size=0.5),
        plot.title=element_text(face="bold",color="red",size=14),
        legend.title = element_text(colour="black", size=26,face="bold"),
        legend.text = element_text(colour="black", size=18))+
  labs(x = "address",y = "")

Answer 1

This solution makes each group unique and arranges in the desired order, then changes the names back to your original names.

df_ex$names<-paste(df_ex$address,df_ex$clas,df_ex$No)
df_ex$names<-factor(df_ex$names,levels=c("A Good 1","B Ugly 1","C Ugly 1", "A Good 2", "C Bad 2", "B Ugly 2", "C Good 3", "A Bad 3", "B Bad 3"))


ggplot(df_ex, aes(x=names,y="",fill=clas)) + #x axis bias voltage dependence
  geom_tile() + 
  scale_fill_manual(values=c('Good'="green","Bad"="Blue","Ugly"="black"))+
  facet_wrap(~No,ncol=1,scales = "free_x")+
  theme(legend.position = "top",axis.text.y = element_text(size = 20,angle = 90),axis.text.x = element_text(size=12,face="bold",colour = "black"),
        axis.title.y = element_text(face="bold",size = 20, colour = "black"),
        axis.title.x = element_text(face="bold",size = 20 , colour = "black"),
        strip.text = element_text(size=26, face="bold"),
        strip.background = element_rect(fill="#FFFF66", colour="black", size=0.5),
        plot.title=element_text(face="bold",color="red",size=14),
        legend.title = element_text(colour="black", size=26,face="bold"),
        legend.text = element_text(colour="black", size=18))+
  labs(x = "address",y = "")+
  scale_x_discrete(breaks=df_ex$names, labels=df_ex$address)