Plotly R-交互式滤镜和按组离散的颜色

Question

I'm having some troubles with plotly in R. I am creating an rmarkdown, and am making use of the updatemenus & transforms feature to add a drop down. I've made some dummy data to highlight the problem that I have.

I want to be able to control the colours in a discrete way. I have 3 individuals in each group, and I want them to have the same set of colours when you change group. so colour of a = colour of d in this case; b=e, c=f.

In reality I have a lot more groups, so when I set this plot up, my colours within a group barely vary, and it looks unprofessional.

Sample code is below, any ideas how to do this would be great. Otherwise I'll have to try rewritting with ggplot and ggplotly which I find look less polished, and I try to use the plotly functions where I can.

library(plotly)
library(RColorBrewer)
# make data. Assign first set a-c to group 1, d-f to group 2
set.seed(1)
df <- data.frame(individual = sample(letters[1:6], 100, replace = TRUE),
                 x = runif(100), stringsAsFactors = FALSE)
groups <- c("g1", "g2")
df$group[match(df$individual, letters) <= 3] <- groups[1]
df$group[match(df$individual, letters) > 3] <- groups[2]
df$y <- df$x*(match(df$individual, letters))
df <- df[order(df$individual),]

# can see data is split ok
table(df$group, df$individual)

# build up interactive element, the filter to the two groups
button_list <- lapply(1:length(groups), function(x){
  list(method = "restyle",
       args = list("transforms[0].value", groups[x]),
       label = groups[x])
})
type_list <-  list(
  type = 'dropdown',
  active = 0,
  xanchor = 'center',
  yanchor = "top",
  pad = list('r'= 0, 't'= 10, 'b' = 10),
  x = 0.5,
  y = 1.27,
  buttons = button_list
)

# make plot, color based on the individual in the group
plot_ly(df, x = ~x, y = ~y, mode = "lines+markers",
        color = ~ individual, 
        colors = brewer.pal(3, "Set1"),
        hoverinfo = "text", text = ~paste(individual),
        transforms = list(
          list(
            type = 'filter',
            target = ~group,
            operation = '=',
            value = df$group[1]
          ))
        ) %>%
          layout(updatemenus = list(
                   type_list
                 ))

Cheers

Answer 1

快速又脏：用“允许的”颜色填充颜色

colors = rep( brewer.pal(3, "Set1"), 2)