r - set size of a plot area in ggplot2 -

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• how achieve identical facet sizes , scales in several multi-facet ggplot2 graphics? 1 answer

is there way directly specify width , height of plot area ggplot2, example 3" , 4" figure below?

sample code:

library(ggplot2) x <- seq(-5,5,by=.1) d <- data.frame(x=x,y=cos(x)) p <- ggplot(d) + aes(x=x,y=y) + geom_line() ggsave(p,file='~/example.pdf') 

library(ggplot2) x <- seq(-5,5,by=.1) d <- data.frame(x=x,y=cos(x)) p <- ggplot(d) + aes(x=x,y=y) + geom_line()  pdf(file="example.pdf", width=3, height=4) p dev.off()