R help - Jun 2012 - Adding title to colorkey

A recent paper on visualisation (in Neuron, a leading neuroscience
journal) surveyed how well previous articles in this journal labelled their
graphs (e.g. axis labelling and describing their error bars).  Of
particular interest is that (only) 40% of plots labelled what their
colorkey was showing (variable and units).

The paper is at http://dx.doi.org/10.1016/j.neuron.2012.05.001

R is not yet that prominent (compared to matlab) in Neuroscience, so I
doubt many of the graphs were generated by levelplot() and friends.
However, how can the colorkey be labelled?  I notice that this topic has
been raised before, e.g.

  http://tolstoy.newcastle.edu.au/R/e16/help/11/11/2281.html

For now, I've done:

library(lattice)
library(grid)
levelplot(matrix(1:9,3,3),
          par.settings = list(layout.widths = list(axis.key.padding = 4)))
grid.text('title here', y=unit(0.5, "npc"),
          rot=90, x=unit(0.88, "npc"))

i.e. adding some space between levelplot and colorkey.  The
x,y positions of the grid.text call need fine-tuning once the plot is
close to finalised.  

Does anyone have a better solution for vertical colorkeys?  e.g. can the
plot objected be interrogated to work out what the central x,y value is?


Thanks, Stephen

Stephen, for ggplot2 you might want to check http://goo.gl/0Wx0B

On Sat, Jun 16, 2012 at 4:40 AM, Stephen Eglen
<S.J.Eglen@damtp.cam.ac.uk>wrote:
>
> A recent paper on visualisation (in Neuron, a leading neuroscience
> journal) surveyed how well previous articles in this journal labelled their
> graphs (e.g. axis labelling and describing their error bars).  Of
> particular interest is that (only) 40% of plots labelled what their
> colorkey was showing (variable and units).
>
> The paper is at http://dx.doi.org/10.1016/j.neuron.2012.05.001
>
> R is not yet that prominent (compared to matlab) in Neuroscience, so I
> doubt many of the graphs were generated by levelplot() and friends.
> However, how can the colorkey be labelled?  I notice that this topic has
> been raised before, e.g.
>
>  http://tolstoy.newcastle.edu.au/R/e16/help/11/11/2281.html
>
> For now, I've done:
>
> library(lattice)
> library(grid)
> levelplot(matrix(1:9,3,3),
>          par.settings = list(layout.widths = list(axis.key.padding = 4)))
> grid.text('title here', y=unit(0.5, "npc"),
>          rot=90, x=unit(0.88, "npc"))
>
> i.e. adding some space between levelplot and colorkey.  The
> x,y positions of the grid.text call need fine-tuning once the plot is
> close to finalised.
>
> Does anyone have a better solution for vertical colorkeys?  e.g. can the
> plot objected be interrogated to work out what the central x,y value is?
>
>
> Thanks, Stephen
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]

On Sat, Jun 16, 2012 at 2:10 PM, Stephen Eglen
<S.J.Eglen at damtp.cam.ac.uk> wrote:
>
> A recent paper on visualisation (in Neuron, a leading neuroscience
> journal) surveyed how well previous articles in this journal labelled their
> graphs (e.g. axis labelling and describing their error bars). ?Of
> particular interest is that (only) 40% of plots labelled what their
> colorkey was showing (variable and units).
>
> The paper is at http://dx.doi.org/10.1016/j.neuron.2012.05.001
>
> R is not yet that prominent (compared to matlab) in Neuroscience, so I
> doubt many of the graphs were generated by levelplot() and friends.
> However, how can the colorkey be labelled? ?I notice that this topic has
> been raised before, e.g.
>
> ?http://tolstoy.newcastle.edu.au/R/e16/help/11/11/2281.html
>
> For now, I've done:
>
> library(lattice)
> library(grid)
> levelplot(matrix(1:9,3,3),
> ? ? ? ? ?par.settings = list(layout.widths = list(axis.key.padding = 4)))
> grid.text('title here', y=unit(0.5, "npc"),
> ? ? ? ? ?rot=90, x=unit(0.88, "npc"))
>
> i.e. adding some space between levelplot and colorkey. ?The
> x,y positions of the grid.text call need fine-tuning once the plot is
> close to finalised.
>
> Does anyone have a better solution for vertical colorkeys? ?e.g. can the
> plot objected be interrogated to work out what the central x,y value is?
This is slightly simpler:

levelplot(matrix(1:9,3,3), ylab.right = "title here",
          par.settings = list(layout.widths = list(axis.key.padding = 0,
                                                   ylab.right = 2)))

There really should be a function allowing easy construction of
complex legends combining simpler ones. There is currently only
mergedTrellisLegendGrob in latticeExtra (not very robust) which can be
used as follows:

library(latticeExtra)

p <- levelplot(matrix(1:9,3,3))
p$legend$right <-
    list(fun = mergedTrellisLegendGrob(p$legend$right,
                                       list(fun = textGrob,
                                            args = list("title here",
rot = -90)),
                                       vertical = FALSE))
p

-Deepayan