[R] stacked bar on single-color printing

[Greg Snow]

While it is possible to fill bars with patterns, it is not
recommended.  Fill patterns can lead to what is called the Moire
effect and other optical illusions.  Depending on the fill patterns
and how they relate to each other this can cause an illusion of
movement within the plot, straight lines appearing curved, and
distorting of lengths/positions.  Fill patterns (through the
illusions) can subtly move the observer's eye away from the important
parts of a graph and make it hard to focus on the parts of the graph
that are most important.  Google for phrases "Moire effect graphs" and
"optical illusion diagonal lines" for some examples.

Perhaps a dot chart (using symbols instead of colors/greyscale/fill
patterns) would be a better option than a bar chart for your case.

On Thu, Aug 13, 2020 at 7:21 AM John <miaojpm using gmail.com> wrote:
>
> Thanks Rui. That's very close to what I am looking for. You use gray scales
> for different categories. That would be a great idea. Could we use pattern
> fill?
> Rui Barradas <ruipbarradas using sapo.pt> 於 2020年8月13日 週四 下午6:31寫道：
>
> > Hello,
> >
> > Without sample data and the code you've tried it's difficult to say but
> > are you looking for something like this?
> >
> >
> > set.seed(2020)
> > df1 <- expand.grid(X = factor(1:5), Y = LETTERS[1:2])
> > df1 <- df1[sample(nrow(df1), 100, TRUE), ]
> >
> > library(ggplot2)
> >
> > tbl <- as.data.frame(table(df1))
> >
> > ggplot(tbl, aes(X, Freq, color = Y, fill = Y)) +
> >    geom_col() +
> >    scale_color_manual(values = c("black", "black")) +
> >    scale_fill_manual(values = c("white", "gray70")) +
> >    theme_bw()
> >
> >
> > Hope this helps,
> >
> > Rui Barradas
> >
> > Às 10:05 de 13/08/20, John escreveu:
> > > Hi,
> > >
> > >     I would like to create percentage stacked bar with graphics package
> > > (e.g., ggplot2) and print it in white/black. The regular option is to use
> > > different color on the bar. Is there any way to use different background
> > on
> > > a bar so that we can tell on a black/white printing? For example, let my
> > > green correspond to ***, while my red correspond to ....
> > >
> > >     Thanks,
> > >
> > > J
> > >
> > >       [[alternative HTML version deleted]]
> > >
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> > >
> >
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
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-- 
Gregory (Greg) L. Snow Ph.D.
538280 using gmail.com