Display y-axis for each subplot when faceting

Question

I am plotting three plots next to each other using facet_grid.

Facet grid will only draw the y-axis for the first plot. Is there a way to draw the y-axis for all thr

Answer 1

You can copy the (part of the) y-axis and place copies for each panel,

g <- ggplotGrob(plot1)

require(gtable)
axis <- gtable_filter(g, "axis-l")[["grobs"]][[1]][["children"]][["axis"]][,2]
segment <- segmentsGrob(1,0,1,1)
panels <- subset(g$layout, name == "panel")
g <- gtable_add_grob(g, grobs=list(axis, axis), name="ticks",
                     t = unique(panels$t), l=tail(panels$l, -1)-1)

g <- gtable_add_grob(g, grobs=list(segmentsGrob(1,0,1,1), 
                                   segmentsGrob(1,0,1,1)), 
                     t = unique(panels$t), l=tail(panels$l, -1)-1, 
                     name="segments")
grid.newpage()
grid.draw(g)