Violin plot with mean_sdl

Hi,

I followed the example described at [1] but I don't know why I get the following warning

library(ggplot2)
library(Hmisc)
mydata <- read.csv('test.csv', header=T,row.names=1)
mydata

V1  V2   V3 V4
P1 73.6 0.7 74.6  R
P2 75.2 0.7 75.8  R
P3  6.5 0.0  7.3  R
P4 41.4 0.3 39.2  C
P5  5.4 0.1 18.2  C
P6 18.8 0.3 30.3  C

p <- ggplot(mydata, aes(x=V4, y=V1)) + geom_violin(trim=FALSE)
p + stat_summary(fun.data="mean_sdl", mult=1,

+                  geom="crossbar", width=0.2 )
Warning message:
Ignoring unknown parameters: mult


How can I fix that?



[1] http://www.sthda.com/english/wiki/ggplot2-violin-plot-quick-start-guide-r-software-and-data-visualization


Regards,
Mahmood