Plotly（R）-饼图：如何固定每组的颜色分配颜色？

debugcn 发表于 Dev

斯坦·W

我们正在构建一个Shiny应用程序，其中使用了动态绘图饼图。用户可以选择要包含在图中的变量。

添加自定义颜色代码使我可以添加自定义颜色，但是它们不会像在散布条形图中一样（使用colors命令）坚持分组变量。

例：

library(plotly)

dat <- data.frame(dis = c(1,2,3), value = c(20,30,24))

plot_ly(dat, labels = ~dis, values = ~value, sort = F, 
        marker = list(colors = c("1" = "#B76C9E", 
                                 "2" = "#4285F4",
                                 "3" = "#EA4335"))) %>%
  add_pie(hole = 0.3) %>%
  layout(legend = list(orientation = 'h'), margin = list(l = 0 , r = 0, t = 0, b = 100, pad = 1),
         yaxis = list(showgrid = FALSE, zeroline = FALSE, showticklabels = FALSE))

但是，当我从data.frame中删除dis == 1时（就像我的用户在Shiny应用程序中所做的那样），颜色会发生变化，并且不会保持分配的颜色：

dat2 <- data.frame(dis = c(2,3), value = c(30,24))

plot_ly(dat2, labels = ~dis, values = ~value, sort = F, 
        marker = list(colors = c("1" = "#B76C9E", 
                                 "2" = "#4285F4",
                                 "3" = "#EA4335"))) %>%
  add_pie(hole = 0.3) %>%
  layout(legend = list(orientation = 'h'), margin = list(l = 0 , r = 0, t = 0, b = 100, pad = 1),
         yaxis = list(showgrid = FALSE, zeroline = FALSE, showticklabels = FALSE))

有没有一种方法可以将颜色锁定到分类变量，这样“ 2”将始终获得相同的颜色？

笨狼

我想您必须通过更新呼叫中的颜色，像这样..但是我认为这很粗糙：

pal = c("#B76C9E", "#4285F4","#EA4335")
names(pal) = as.character(1:3)

updated_pal = pal[unique(as.character(dat2$dis))]

plot_ly(dat2, 
labels = ~dis, values = ~value, sort = F,
marker=list(colors=updated_pal)) %>%
  add_pie(hole = 0.3) %>%
  layout(legend = list(orientation = 'h'), margin = list(l = 0 , r = 0, t = 0, b = 100, pad = 1),
         yaxis = list(showgrid = FALSE, zeroline = FALSE, showticklabels = FALSE))