[R] geom_text only in the first panel with facet_wrap in ggplot2

[Maria Lathouri]

Dear all, 


I am trying to add text only in the first panel of a faceted ggplot; I have been struggling to find a solution on this online but unfortunately none of what I found is working. 

Here it is a reproducible example. I hope it helps: 
library(gamm4) 
library(ggplot2) 

example<-read.csv("example.csv") 

head(example) 
#  Q  index ASB Year       WB_ID  S_ID score_1 score_2 works 
#1 100  1.02  1 2011 CL102021072830 157166     0   2.83    0 
#2 100  1.03  1 2014 CL102021072830 157166     0   2.83    0 
#3  80  1.02  1 2013 CL102021072860  1636     0  10.39    0 
#4  80  1.06  2 2006 CL102021072860  1636     0  10.39    0 
#5  80  1.06  2 2003 CL102021072860  1636     0  10.39    0 
#6  98  1.07  3 2002 CL102021072900  1635     0   7.57    0 

str(example) 
#'data.frame':    249 obs. of  9 variables: 
#  $ Q    : int  100 100 80 80 80 98 105 105 105 105 ... 
#$ index  : num  1.02 1.03 1.02 1.06 1.06 1.07 1.14 1.05 1.1 1.08 ... 
#$ ASB   : int  1 1 1 2 2 3 1 1 3 3 ... 
#$ Year  : int  2011 2014 2013 2006 2003 2002 2013 2005 2013 2006 ... 
#$ WB_ID  : Factor w/ 44 levels "CL102021072830",..: 1 1 2 2 2 3 3 3 4 4 ... 
#$ S_ID  : int  157166 157166 1636 1636 1636 1635 1635 1635 134261 1631 ... 
#$ score_1: int  0 0 0 0 0 0 0 0 0 0 ... 
#$ score_2: num  2.83 2.83 10.39 10.39 10.39 ... 
#$ works  : num  0 0 0 0 0 0 0 0 0 0 ... 

# I need first to run a mixed-effect model
model<-gamm4(index~s(Q, by=factor(ASB))+Year+score_1+score_2+works, data=example, random=~(1|WB_ID/S_ID)) 


#I had to create a new dataset so I can use this with the ggplot2
newDat <- expand.grid(ASB = factor(example$ASB), 
Q = seq(from = min(example$Q, na.rm = TRUE), 
to = max(example$Q, na.rm = TRUE), 
length = 100), 
Year = 2002, 
score_1 = mean(example$score_1), 
score_2 = mean(example$score_2), 
works = mean(example$works), 
WB_ID = "CL102021072830", 
S_ID = "157166") 

datM <- predict(model$gam, type = "response", 
se.fit = TRUE, newdata = newDat) 

newDat$fit <- datM$fit 
newDat$upr <- datM$fit + (1.96 * datM$se.fit) 
newDat$lwr <- datM$fit - (1.96 * datM$se.fit) 



#I create a new variable for ASB so I can change the panel text
newDat$asb_1<-factor(newDat$ASB, levels=c(1, 2, 3), labels=c("ASB1", "ASB2", "ASB3")) 


#I plot this with ggplot2
p<-ggplot(newDat, aes(x = Q, y = fit, group = ASB)) + 
theme_bw() + 
geom_rug(data = example, aes(x = Q, y = 0.96), sides = "b") + 
ylim(0.96, 1.04) + 
geom_ribbon(aes(ymin = lwr, ymax = upr), col = NA, fill = "grey", 
alpha = 0.3) + 
geom_line(size = 1) + 
facet_wrap(~ asb_1, labeller = label_parsed) 


#When I try to add the text through geom_text, I get the text to all the three panels 
dat_text <- data.frame(label = c("Text", " ", " "), ASB  = c(1, 2, 3)) 

p + geom_text(x=20, y=1.03, data = dat_text, label = label) 

# or
p+geom_text(x=20, y=1.03 , aes(label=label), data=dat_text)


# I tried another way
ann_text <- data.frame(Q = 20, fit = 1.03, lab = "Text", ASB = factor(1,levels = c("1","2","3"))) 

p + geom_text(data = ann_text, label = "Text") 


# When I tried to use asb_1 instead of ASB, I got an errorann_text <- data.frame(Q = 20, fit = 1.03, lab = "Text", asb = factor("ASB1",levels = c("1","2","3"))) 


#Error in FUN(X[[i]], ...) : object 'ASB' not found

I would very much appreciate for your help. 

Thank you very much in advance. 

Kind regards,
Maria