将图例添加到geom_segement

Question

如何在标题为＆＃34;工作单＆＃34;下面的geom_segement图中添加标题。标题下面有一个红线，文字为＃34; Type 1＆＃34;和带文字的蓝线＆＃34;类型2＆＃34;？

谢谢。

 df = data.frame(time1=as.POSIXct(c("2012-04-04 09:23:33","2012-04-04 11:33:55")),
                  time2=as.POSIXct(c("2012-04-04 10:05:04","2012-04-04 13:42:24")), 
                  y1=c(1,2),
                  y2=c(1,2),
                  color = c("red","blue"))
ggplot(df)  + geom_segment(aes(x = time1, y = y1, xend = time2, yend = y2), 
             colour= df$color, size = 4, data = df)

Answer 1

将分组变量映射到color中的aes，并在scale_color_manual中设置名称，值，分隔符和标签。

ggplot(df)  + 
    geom_segment(aes(x = time1, y = y1, xend = time2, yend = y2, color = color), 
               size = 4, data = df) +
    scale_color_manual(name = "work order", values = c("blue", "red"), 
                    breaks = c("red", "blue"), labels = c("Type 1", "Type 2"))

您还可以使用scale_color_identity，它允许跳过值的设置，但您需要包含guide = "legend"，因为它默认为"none"。

ggplot(df)  + 
    geom_segment(aes(x = time1, y = y1, xend = time2, yend = y2, color = color), 
               size = 4, data = df) +
    scale_color_identity(name = "work order", guide = "legend",  
                    breaks = c("red", "blue"), labels = c("Type 1", "Type 2"))