[R] Patch for legend.position={left,top,bottom} in ggplot2

[Karsten Loesing]

Hi everyone,

here's the same patch as a new branch on GitHub.

  http://github.com/kloesing/ggplot2/commit/a25e4fbfa4017ed1

Best,
--Karsten


On 6/7/10 3:39 PM, Karsten Loesing wrote:
> Hi Hadley and everyone,
> 
> here's a patch for ggplot2 that fixes the behavior of
> opts(legend.position={left,top,bottom}). If you try the following code
> in an unmodified ggplot2
> 
> options(warn = -1)
> suppressPackageStartupMessages(library("ggplot2"))
> data <- data.frame(
>     x = c(1, 2, 3, 4, 5, 6),
>     y = c(2, 3, 4, 3, 4, 5),
>     colour = c(TRUE, TRUE, TRUE, FALSE, FALSE, FALSE))
> ggplot(data, aes(x = x, y = y, colour = colour)) +
>     geom_line() + opts(title = "title", legend.position = "right")
> ggplot(data, aes(x = x, y = y, colour = colour)) +
>     geom_line() + opts(title = "title", legend.position = "left")
> ggplot(data, aes(x = x, y = y, colour = colour)) +
>     geom_line() + opts(title = "title", legend.position = "top")
> ggplot(data, aes(x = x, y = y, colour = colour)) +
>     geom_line() + opts(title = "title", legend.position = "bottom")
> 
> you'll see that plots 2 to 4 are broken.
> 
> I think I located the bug in surround_viewports() where the graphical
> elements are placed into the grid. If we increment all rows and columns
> of the graphical elements for positions "left", "top", and "bottom" by
> 1, those graphs look sane again. I assume that a new first row and
> column were added at some point in the development, but only the
> parameters for the default position "right" were adjusted. Here's the patch:
> 
> 
> --- ggplot2-orig2	2010-06-07 13:14:35.000000000 +0200
> +++ ggplot2	2010-06-07 15:22:33.000000000 +0200
> @@ -7003,27 +7003,27 @@
>      )
>    } else if (position == "left") {
>      viewports <- vpList(
> -      vp("panels", 2, 3),
> -      vp("legend_box", 2, 1),
> -      vp("ylabel", 2, 2),
> -      vp("xlabel", 3, 3),
> -      vp("title", 1, 3)
> +      vp("panels", 3, 4),
> +      vp("legend_box", 3, 2),
> +      vp("ylabel", 3, 3),
> +      vp("xlabel", 4, 4),
> +      vp("title", 2, 4)
>      )
>    } else if (position == "top") {
>      viewports <- vpList(
> -      vp("panels", 3, 2),
> -      vp("legend_box", 2, 2),
> -      vp("ylabel", 3, 1),
> -      vp("xlabel", 4, 2),
> -      vp("title", 1, 2)
> +      vp("panels", 4, 3),
> +      vp("legend_box", 3, 3),
> +      vp("ylabel", 4, 2),
> +      vp("xlabel", 5, 3),
> +      vp("title", 2, 3)
>      )
>    } else if (position == "bottom") {
>      viewports <- vpList(
> -      vp("panels", 2, 2),
> -      vp("legend_box", 4, 2),
> -      vp("ylabel", 2, 1),
> -      vp("xlabel", 3, 2),
> -      vp("title", 1, 2)
> +      vp("panels", 3, 3),
> +      vp("legend_box", 5, 3),
> +      vp("ylabel", 3, 2),
> +      vp("xlabel", 4, 3),
> +      vp("title", 2, 3)
>      )
>    } else {
>      viewports <- vpList(
> 
> 
> Best,
> --Karsten
>