I am trying to create a function in R that turns the colors of a plot into colors that are colorblind friendly. According to my assignment, the function should perform an operation that solves a specific problem that you can and will demonstrate using multiple coding examples. You will be graded on how integrative your function is; do you combine multiple concepts to solve a problem? A function doing simple math $($e$.$g$.,$ adding one to a number$)$ will not be deemed acceptable.

Your function should have at least two arguments. Your function must include and demonstrate competency in more than one of these topics.

$$ operators

$$ the family of dplyr data wrangling functions in the tidyverse

$$ the pipe operator

$$ ggplot$2$ data visualization in the tidyverse

$$ joining data

$$ pivoting data

$$ grouping data

$$ iteration $($for loops or sapply and lapply$)$

$$ dataframes, vectors, and lists

My code is as follows:

colorblind$\_$friendly$\_$plot $<-$ function$($plot$,$ palette $=$ "viridis"$)\{$

library$($ggplot$2)$

library$($viridis$)$

data $<-$ ggplot$\_$build$($plot$)$$data

unique$\_$colors $<-$ unique$($unlist$($lapply$($data$,$ function$($x$)$ x$fill$)))$

colors $<-$ viridis$\_$pal$($palette$)($n $=$ length$($unique$\_$colors$))$

plot $<-$ plot $+$

scale$\_$fill$\_$manual$($values $=$ colors$)+$

scale$\_$color$\_$manual$($values $=$ colors$)$

return$($plot$)$

$\}$

However, I keep getting the error "Error in grDevices::rgb$($cols$[,1],$ cols$[,2],$ cols$[,3],$ alpha $=$ alpha$)$ : alpha level NA$,$ not in $[0,1]"$ when I try to run my code using an example. Does anyone have any suggestions on how to fix my code?