r - 将特定图例添加到 R plotly 图表

Question

有人知道是否可以将以下类型的图例添加到 R plot_ly 图表中？

请在下面找到一个可复制的示例

在这个例子中，条形颜色取决于速度值：我想打印上面提到的图例，而不仅仅是得到“trace 0”......

library(plotly)
library(data.table)

example_data <- data.table(x = c(1,2,3,4,5,6), y = c(7,9,4,3,8,9), velocity = c(0.6,1.4,5,4,0.2,1.1))
example_data$color <- cut(example_data$velocity,breaks = c(0,0.8,1.2,1.5,10),labels = c("lightgreen","darkgreen","yellow","red"))

plot_ly(data = example_data, x = ~ x,y =  ~y ,color =  ~ I(color),type = "bar") %>% 
  layout(showlegend = TRUE)

非常感谢 ！

标签： rcolorslegendr-plotly

Answer 1

您可以使用图例的名称创建一个新列。并将因子重新排序为从低 (0 - 0.8) 到高 (> 1.5)。

你可以试试这个：

example_data <- data.table(x = c(1,2,3,4,5,6), y = c(7,9,4,3,8,9), velocity = c(0.6, 1.4, 5, 4, 0.2, 1.1), 
                           name = c("0 - 0.8", "1.2 - 1.5", " >1.5", " >1.5", "0 - 0.8", "0.8 - 1.2"))

example_data$name <- as.factor(example_data$name)
example_data$name <- factor(example_data$name, levels = c("0 - 0.8", "0.8 - 1.2", "1.2 - 1.5", " >1.5"))

pal <- c("lightgreen", "darkgreen", "yellow", "red")

plot_ly(data = example_data, x = ~ x,y =  ~y ,color =  ~as.factor(name), colors = ~pal, type = "bar") %>% 
  layout(showlegend = TRUE, legend = list(orientation = "h",
                                          xanchor = "center",  
                                          x = 0.5, y = 7))