R help - Apr 2021 - Weighted violin chart

Hi,

I would like to know if it is possible to plot a weighted violin chart with R.
Currently, I have

> library(ggplot2)
> mydata <- read.csv('test.csv', header=T,row.names=1)
> mydata
     V1 V2 V3
P1 73.6 50  R
P2 75.2 20  R
P3  6.5  5  R
P4 41.4 10  C
P5  5.4 10  C
P6 18.8  5  C
> p <- ggplot(mydata, aes(x=V3, y=V1)) + geom_violin(trim=FALSE)
> p + geom_dotplot(binaxis='y', stackdir='center', dotsize=1)
I would like to use V2 as the weight vector. Any idea about that?



Regards,
Mahmood

	[[alternative HTML version deleted]]

----- Original Message -----
> From: "Mahmood Naderan-Tahan" <mahmood.naderan at ugent.be>
> To: r-help at r-project.org
> Sent: Monday, 12 April, 2021 21:01:18
> Subject: [R] Weighted violin chart
> Hi,
> 
> I would like to know if it is possible to plot a weighted violin chart with
R.
> Currently, I have
> 
> 
>> library(ggplot2)
>> mydata <- read.csv('test.csv', header=T,row.names=1)
>> mydata
>     V1 V2 V3
> P1 73.6 50  R
> P2 75.2 20  R
> P3  6.5  5  R
> P4 41.4 10  C
> P5  5.4 10  C
> P6 18.8  5  C
>> p <- ggplot(mydata, aes(x=V3, y=V1)) + geom_violin(trim=FALSE)
>> p + geom_dotplot(binaxis='y', stackdir='center',
dotsize=1)
> 
> I would like to use V2 as the weight vector. Any idea about that?
> 
> 
> 
> Regards,
> Mahmood
There are, of course, nice ways to do this using base R but I am trying to
convert to using tidyverse.
Here is one:

### use tribble to create a tibble rowwise
tribble(
  ~V1, ~V2, ~V3,
  73.6, 50, "R",
  75.2, 20, "R",
  6.5, 5, "R",
  41.4, 10, "C",
  5.4, 10, "C",
  18.8, 5, "C") -> myData

### use tidyr::uncount() to get to the data you want
myData %>%
  uncount(V2) -> tibWtdMyData

### plot it 
ggplot(tibWtdMyData, 
       aes(x=V3, y=V1)) + 
  geom_violin(trim=FALSE) +
  geom_dotplot(binaxis='y', stackdir='center', dotsize=1)

Of course, with so many identical values, I'm not sure a violin plot makes
sense but perhaps you
were showing us a small subset of your data.

I have a nasty feeling there is a way of weighting things within ggplot.  If so,
I am sure someone
will tell us.

For future, it's much easier for us to reply if you put small bits of data
like your myData into
your Email using dput.  The output from dput doesn't look terribly human
friendly but unless it
is mangled by HTML Emailing, it is wonderfully human friendly to use!

Very best (all),

Chris


-- 
Chris Evans (he/him) <chris at psyctc.org> Visiting Professor, University
of Sheffield <chris.evans at sheffield.ac.uk>
I do some consultation work for the University of Roehampton <chris.evans at
roehampton.ac.uk> and other places
but <chris at psyctc.org> remains my main Email address.  I have a work
web site at:
   https://www.psyctc.org/psyctc/
and a site I manage for CORE and CORE system trust at:
   http://www.coresystemtrust.org.uk/
I have "semigrated" to France, see: 
   https://www.psyctc.org/pelerinage2016/semigrating-to-france/ 
  
https://www.psyctc.org/pelerinage2016/register-to-get-updates-from-pelerinage2016/

If you want an Emeeting, I am trying to keep them to Thursdays and my diary is
at:
   https://www.psyctc.org/pelerinage2016/ceworkdiary/
Beware: French time, generally an hour ahead of UK.

Hi again,

As a follow up, does anybody know how to fix the following error?

It seems that I can use a "weight" parameter in geom_violin, but I am
able to  figure out what is the problem with the following code.


> library(ggplot2)
> mydata <- read.csv('test.csv', header=T,row.names=1)
> mydata
     V1 V2 V3
P1 73.6 50  R
P2 75.2 20  R
P3  6.5  5  R
P4 41.4 10  C
P5  5.4 10  C
P6 18.8  5  C
> p <- ggplot(mydata, aes(x=V3, y=V1)) + geom_violin(trim=FALSE,
weight=V2)
Error in layer(data = data, mapping = mapping, stat = stat, geom = GeomViolin, 
:
  object 'V2' not found
>
>
> wg <- as.factor(mydata$V2)
> p <- ggplot(mydata, aes(x=V3, y=V1)) + geom_violin(trim=FALSE,
weight=wg)
> p + geom_dotplot(binaxis='y', stackdir='center', dotsize=1)
`stat_bindot()` using `bins = 30`. Pick better value with `binwidth`.
Error: Aesthetics must be either length 1 or the same as the data (1024): weight
Run `rlang::last_error()` to see where the error occurred.





Regards,
Mahmood


________________________________
From: Mahmood Naderan-Tahan
Sent: Monday, April 12, 2021 10:01 PM
To: r-help at r-project.org
Subject: Weighted violin chart


Hi,

I would like to know if it is possible to plot a weighted violin chart with R.
Currently, I have

> library(ggplot2)
> mydata <- read.csv('test.csv', header=T,row.names=1)
> mydata
     V1 V2 V3
P1 73.6 50  R
P2 75.2 20  R
P3  6.5  5  R
P4 41.4 10  C
P5  5.4 10  C
P6 18.8  5  C
> p <- ggplot(mydata, aes(x=V3, y=V1)) + geom_violin(trim=FALSE)
> p + geom_dotplot(binaxis='y', stackdir='center', dotsize=1)
I would like to use V2 as the weight vector. Any idea about that?



Regards,
Mahmood

	[[alternative HTML version deleted]]