R help - May 2018 - draw borders of bars inside of the rectangles in a barplot

Dear R-users,

I want to draw a barplot with beside=TRUE.
One halve of the bars are drawn with a border, while the other halve are drawn
without a border (i.e. filled bars vs. non-filled bars next to each other).

Because borders are drawn around the bars, doing this leads to one halve of the
bars being wider than the other halve, expanding across the 0-point of the
y-axis.
This problem emerges especially with small figures and rather large border
width.

Now my question:
Is there a way to draw the border inside of the bars instead of surrounding the
bars? (similar to border-drawing options in graphics software, like photoshop or
inkscape).


Here some example code:

x <- matrix(c(1:10), 2,5)
par(lwd = 5) 
barplot(x, beside=T, border=rep(c(NA, 'black'),5), space=c(0.08,1),
col=rep(c('black', 'white'),5))



Thank you!

As I read ?barplot, the answer is no. I suspect the same is true in ggplot
and lattice, but you would have to check. If correct, this means you would
explicitly have to use the "width" argument to narrow or widen the
bars
appropriately. Or maybe try something like:

barplot(x, beside=T, border= "black", space=c(0.08,1),
col=rep(c('gray50',
'white'),5))

instead.

Cheers,
Bert



Bert Gunter

"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )

On Mon, May 21, 2018 at 7:59 AM, Martin Batholdy via R-help <
r-help at r-project.org> wrote:
> Dear R-users,
>
> I want to draw a barplot with beside=TRUE.
> One halve of the bars are drawn with a border, while the other halve are
> drawn without a border (i.e. filled bars vs. non-filled bars next to each
> other).
>
> Because borders are drawn around the bars, doing this leads to one halve
> of the bars being wider than the other halve, expanding across the 0-point
> of the y-axis.
> This problem emerges especially with small figures and rather large border
> width.
>
> Now my question:
> Is there a way to draw the border inside of the bars instead of
> surrounding the bars? (similar to border-drawing options in graphics
> software, like photoshop or inkscape).
>
>
> Here some example code:
>
> x <- matrix(c(1:10), 2,5)
> par(lwd = 5)
> barplot(x, beside=T, border=rep(c(NA, 'black'),5), space=c(0.08,1),
> col=rep(c('black', 'white'),5))
>
>
>
> Thank you!
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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]]

I recommend instead of no border, that you use a border with the same
color as the fill.
I do this in the likert functions in the HH package.

Rich


On Mon, May 21, 2018 at 10:59 AM, Martin Batholdy via R-help
<r-help at r-project.org> wrote:
> Dear R-users,
>
> I want to draw a barplot with beside=TRUE.
> One halve of the bars are drawn with a border, while the other halve are
drawn without a border (i.e. filled bars vs. non-filled bars next to each
other).
>
> Because borders are drawn around the bars, doing this leads to one halve of
the bars being wider than the other halve, expanding across the 0-point of the
y-axis.
> This problem emerges especially with small figures and rather large border
width.
>
> Now my question:
> Is there a way to draw the border inside of the bars instead of surrounding
the bars? (similar to border-drawing options in graphics software, like
photoshop or inkscape).
>
>
> Here some example code:
>
> x <- matrix(c(1:10), 2,5)
> par(lwd = 5)
> barplot(x, beside=T, border=rep(c(NA, 'black'),5), space=c(0.08,1),
col=rep(c('black', 'white'),5))
>
>
>
> Thank you!
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.

Hi

In addition to Richard's suggestion to add borders to the "only
filled"
bars, you could add "mitred" corners, like this ...


par(ljoin="mitre")
barplot(x, beside=T, border=rep(c('black', 'black'),5),
         space=c(0.08,1), col=rep(c('black', 'white'),5))


It may be overkill, but if the "bleeding" below y=0 is still a bother,
here's one way you could then clip the bar bottoms ...


par(lwd=5, ljoin="mitre")
barplot(x, beside=T, border=rep(c('black', 'black'),5),
         space=c(0.08,1), col=rep(c('black', 'white'),5))
## Convert to 'grid'
library(gridGraphics)
grid.echo()
## Which grob is the bars?
barpath <- grid.grep("rect", grep=TRUE, viewports=TRUE)
## Which viewport are the bars drawn within?
barvp <- attr(barpath, "vp")
## Get copy of the bars
bars <- grid.get(barpath)
## Remove the bars
grid.remove(barpath)
## Go to the bars viewport
downViewport(barvp)
## Set up a clipping rect
grid.clip(y=unit(0, "native"),
           height=unit(11, "native"),
           just="bottom",
           name="clip")
## Draw the bars again (now clipped)
grid.draw(bars)


You could take it even further and clip each individual bar (so the 
border is only visible "inside" the bar) ...


par(lwd=5, ljoin="mitre")
barplot(x, beside=T, border=rep(c('black', 'black'),5),
         space=c(0.08,1), col=rep(c('black', 'white'),5))
library(gridGraphics)
grid.echo()
barpath <- grid.grep("rect", grep=TRUE, viewports=TRUE)
barvp <- attr(barpath, "vp")
bars <- grid.get(barpath)
grid.remove(barpath)
downViewport(barvp)
## Filled bars
for (i in 1:5) {
     odd <- i*2 - 1
     grid.rect(bars$x[odd], bars$y[1], bars$width[odd], bars$height[odd],
               just=c("left", "bottom"),
gp=gpar(fill="black"))
}
## Border bars (clipped)
for (i in 1:5) {
     even <- i*2
     grid.clip(bars$x[even], bars$y[1],
               bars$width[even], bars$height[even],
               just=c("left", "bottom"))
     grid.rect(bars$x[even], bars$y[2],
               bars$width[even], bars$height[even],
               just=c("left", "bottom"), gp=gpar(lwd=5))
}


And, since you mentioned Photoshop/Inkscape, another option to draw 
borders only "inside" the bars is a "variable-width line"
from the
'vwline' package ...


par(lwd=5, ljoin="mitre")
barplot(x, beside=T, border=rep(c('black', 'black'),5),
         space=c(0.08,1), col=rep(c('black', 'white'),5))
library(gridGraphics)
grid.echo()
barpath <- grid.grep("rect", grep=TRUE, viewports=TRUE)
barvp <- attr(barpath, "vp")
bars <- grid.get(barpath)
grid.remove(barpath)
downViewport(barvp)
## Filled bars
for (i in 1:5) {
     odd <- i*2 - 1
     grid.rect(bars$x[odd], bars$y[1], bars$width[odd], bars$height[odd],
               just=c("left", "bottom"),
gp=gpar(fill="black"))
}
## Draw vwline with width only "inside"
library(vwline)
for (i in 1:5) {
     even <- i*2
     left <- bars$x[even]
     right <- bars$x[even] +
         convertUnit(bars$width[even], "in",
                     "x", "dimension", "x",
"location")
     bottom <- bars$y[2]
     top <- bars$y[2] +
         convertUnit(bars$height[even], "in",
                     "y", "dimension", "y",
"location")
     grid.vwline(unit.c(left, left, right, right),
                 unit.c(bottom, top, top, bottom),
                 w=widthSpec(list(left=rep(0, 4),
                                  right=unit(rep(1, 4), "mm"))),
                 open=FALSE)
}


Paul

On 22/05/18 04:05, Richard M. Heiberger wrote:
> I recommend instead of no border, that you use a border with the same
> color as the fill.
> I do this in the likert functions in the HH package.
> 
> Rich
> 
> 
> On Mon, May 21, 2018 at 10:59 AM, Martin Batholdy via R-help
> <r-help at r-project.org> wrote:
>> Dear R-users,
>>
>> I want to draw a barplot with beside=TRUE.
>> One halve of the bars are drawn with a border, while the other halve
are drawn without a border (i.e. filled bars vs. non-filled bars next to each
other).
>>
>> Because borders are drawn around the bars, doing this leads to one
halve of the bars being wider than the other halve, expanding across the 0-point
of the y-axis.
>> This problem emerges especially with small figures and rather large
border width.
>>
>> Now my question:
>> Is there a way to draw the border inside of the bars instead of
surrounding the bars? (similar to border-drawing options in graphics software,
like photoshop or inkscape).
>>
>>
>> Here some example code:
>>
>> x <- matrix(c(1:10), 2,5)
>> par(lwd = 5)
>> barplot(x, beside=T, border=rep(c(NA, 'black'),5),
space=c(0.08,1), col=rep(c('black', 'white'),5))
>>
>>
>>
>> Thank you!
>> ______________________________________________
>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> 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.
> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
> 
-- 
Dr Paul Murrell
Department of Statistics
The University of Auckland
Private Bag 92019
Auckland
New Zealand
64 9 3737599 x85392
paul at stat.auckland.ac.nz
http://www.stat.auckland.ac.nz/~paul/