[R] packGrob and dynamic resizing

[baptiste auguie]

Hi,

I just tried a fourth variant, closer to what ggplot2 uses (I think):
to each grob is assigned a viewport with row and column positions (in
my example during their construction, with ggplot2 upon editing), and
they're all plotted in a given grid.layout. The timing is poor
compared to pushing and upping viewports (twice as long).

Why would that be?

All the best,

baptiste

(the full, self-contained comparison file is attached, run as:

R --vanilla -f comparison.r )

# below is version 4 only

makeContentInVp <- function(d){
content <- as.character(unlist(c(d)))
nc <- ncol(d)
nr <- nrow(d)

n2nm <- function(nr, nc){
expand.grid(seq(1, nr), seq(1, nc))
}

vp.ind <- n2nm(nr, nc)

textii <- function(d, gp=gpar(), name="content-label-"){
  function(ii)
textGrob(label=d[ii], gp=gp,
         name=paste(name, ii, sep=""),
         vp=viewport(layout.pos.row=vp.ind[ii, 1],
layout.pos.col=vp.ind[ii, 2]))
}

 makeOneLabel <- textii(d=content, gp=gpar(col="blue"))

 lg <- lapply(seq_along(content), makeOneLabel)

list(lg=lg, nrow=nrow(d), ncol=ncol(d))
}

## table4 uses grobs that already have a viewport assigned
table4 <- function(content){

padding <- unit(4, "mm")
 lg <- content$lg
 ## retrieve the widths and heights of all textGrobs
  wg <- lapply(lg, grobWidth) # list of grob widths
  hg <- lapply(lg, grobHeight) # list of grob heights

 ## concatenate this units
  widths.all <- do.call(unit.c, wg) # all grob widths
  heights.all <- do.call(unit.c, hg)    #all grob heights

 ## matrix-like operations on units to define the table layout
  widths <- colMax.units(widths.all, content$ncol)  # all column widths
  heights <- rowMax.units(heights.all, content$nrow)  # all row heights


  vp <- viewport(layout=grid.layout(content$nrow,content$ncol,
                   w=widths+padding, h=heights+padding))

        grid.draw(gTree(children=do.call(gList, lg), vp=vp))

}



# uncomment for timing
d <- head(iris)
#d <- iris

content2 <- makeContentInVp(d)

# grid.newpage()
# system.time(table3(content))
##    user  system elapsed
##   4.422   0.091   4.787
 grid.newpage()
system.time(table4(content2))
##    user  system elapsed
##   8.810   0.184   9.555


2009/9/25 hadley wickham <h.wickham at gmail.com>:
>
> This matches my experience with ggplot2 - I have been gradually moving
> away from frameGrob and packGrob because doing the placement myself is
> much faster (and for most of the cases I'm interested in, the full
> power of packGrob is not needed)
>
> Hadley
>
> --
> http://had.co.nz/
>