Adjust widths of multiple plots made by lapply, arrangeGrob - r

Question

I have code to make plots following:
My question is how to adjust the widths of 1st plot and last plot in the figure made?
dat=data.frame(x=rep(c("M","D"),each=60),y=rep(rep(c(4,6,8,10,12),each=12),2),z=runif(120,0,100),s=rep(c(1:4),each=3,len=120))
gp=lapply(split(dat,dat$y),function(dfr){
g=ggplot(data = dfr, aes(s,z)) +
geom_point(aes(shape=x,colour=x),size=4)+
ylim(0,100)+
xlab("Int segs")+
ggtitle(paste(dfr[1,2],"hours"))
return(g)})
tiff(file="Pas.tiff",width=60, height = 22,units="cm",res=300)
require(gridExtra)
rg=arrangeGrob(grobs=list(gp$`4` + theme(legend.position="none"),
gp$`6` + theme(legend.position="none",
axis.title.y = element_blank(),
axis.text.y = element_blank()),
gp$`8` + theme(legend.position="none",
axis.title.y = element_blank(),
axis.text.y = element_blank()),
gp$`10` + theme(legend.position="none",
axis.title.y = element_blank(),
axis.text.y = element_blank()),
gp$`12` + theme(axis.title.y = element_blank(),
axis.text.y = element_blank())),ncol=5,
top=textGrob("Pas rate",
gp=gpar(fontsize=20,fontface="bold"),
y = unit(.4, "cm")),
theme(margin(t=70,r=0.2,b=0.5,l=0.3,unit="mm")))
grid.newpage()
#grid.draw(cbind(lg, rg, size = "last"))
grid.draw(rg)
dev.off()

Answer 1

i'd use cbind() here (if facetting isn't an option)
gp[[1]] <- gp[[1]] + theme(legend.position="none")
gp[[5]] <- gp[[5]] + theme(axis.title.y = element_blank(),
axis.text.y = element_blank())
gp[c("6", "8", "10")] <- lapply(gp[c("6", "8", "10")], "+", e2 = theme(legend.position="none",
axis.title.y = element_blank(),
axis.text.y = element_blank()))
grid.newpage()
grid.draw(do.call(gridExtra::cbind.gtable, lapply(gp, ggplotGrob)))

Answer 2

I suggest you use gtable: you can extract legend and y.label from a first "dummy" plot, then plot each graph within a cell and with the same dimensions (having removed both legend and y.label from all of them, including 1st and last) to then add y.label and legend into separate cells.
require(ggplot2)
require(gtable)
require(grid)
library(dplyr)
library(scales)
dat <- data.frame(x=rep(c("M","D"),each=60),
y=rep(rep(c(4,6,8,10,12),each=12),2),
z=runif(120,0,100),
s=rep(c(1:4),each=3,len=120))
gp <- lapply(split(dat,dat$y),function(dfr){
g=ggplot(data = dfr, aes(s,z)) +
geom_point(aes(shape=x,colour=x),size=4)+
ylim(0,100)+
xlab("Int segs")+
ggtitle(paste(dfr[1,2],"hours"))
return(g)
})
tiff(file="Pas.tiff",width=60, height = 22,units="cm",res=300)
## Step 1:
## "dummy" plot, just to take y axis title/text and legend
dummy <- ggplotGrob(gp[[1]] + theme(panel.background = element_blank()))$grobs
legend <- dummy[[which(sapply(dummy, function(x) x$name) == "guide-box")]]
ytitle <- dummy[[grep("axis.title.y",sapply(dummy, function(x) x$name))]]
yticks <- dummy[[2]]
## Step 2:
## actual plots, all of them without y axis title/text and legend
pp <- 1
tab <- ggplotGrob(gp[[pp]] + theme(legend.position="none",
axis.title.y = element_blank(),
axis.text.y = element_blank()))
for(pp in 2:length(gp)){
tab <- gtable_add_cols(tab, unit(1,"null"))
tab <- gtable_add_grob(tab, ggplotGrob(gp[[pp]] + theme(legend.position="none",
axis.title.y = element_blank(),
axis.text.y = element_blank())),
t = 1, l = ncol(tab), b=nrow(tab), r=ncol(tab))
}
## Step 2:
## adding back ytitle, yticks and legend
## add narrow column to the left and put yticks labels withint
tab <- gtable_add_cols(tab, unit(1,"cm"), pos=0)
tab <- gtable_add_grob(tab, yticks,
t = 3, l = 2, b=nrow(tab)-3, r=1)
## add narrow column to the left and put y.axis label withint
ab <- gtable_add_cols(tab, unit(1,"cm"), pos=0)
tab <- gtable_add_grob(tab, ytitle,
t = 1, l = 1, b=nrow(tab), r=1)
## add narrow column to the right and put legend within
tab <- gtable_add_cols(tab, unit(1.5,"cm"))
tab <- gtable_add_grob(tab, legend,
t = 1, l = ncol(tab), b=nrow(tab), r=ncol(tab))
grid.newpage()
grid.draw(tab)
dev.off()