Align grob at fixed top/center position, regardless of size

Question

I have some table grobs, some long and some short. I\'d like to draw these at the top/center of the page (with a small margin).

From this answer, I got a helpful sta

Answer 1

using the code from the other answer, I get this

library(gridExtra)
justify <- function(x, hjust="center", vjust="center", draw=TRUE){
  w <- sum(x$widths)
  h <- sum(x$heights)
  xj <- switch(hjust,
               center = 0.5,
               left = 0.5*w,
               right=unit(1,"npc") - 0.5*w)
  yj <- switch(vjust,
               center = 0.5,
               bottom = 0.5*h,
               top=unit(1,"npc") - 0.5*h)
  x$vp <- viewport(x=xj, y=yj)
  if(draw) grid.draw(x)
  return(x)
}

library(gridExtra)

tg <- list(tableGrob(iris[1:3, 1:2]), tableGrob(iris[1:5, 1:2]))
tgt <- lapply(tg, justify, vjust="top", draw=FALSE)
grid.newpage()
grid.arrange(grobs=tgt, ncol=2)