在两个y轴上的条形图和折线图中添加图例

问题描述

我绘制了带有两个y轴的条形图和折线图。我正在努力为条形图添加图例。我缩放了第二个y轴，并将比例转换为百分比。我不确定将条形图包含在图例中需要更改什么。另外，我希望从图例名称中删除“颜色”一词。

stockscol <- "#69b3a2"
STUColor <- rgb(0.2,0.6,0.9,1)
WorldSupplyDemand %>%
  select(Year,`EndingStocks(MMT)`,STURatio) %>%
  ggplot() +
  geom_bar(aes(x = Year,y =`EndingStocks(MMT)`),stat = "identity",fill = stockscol,color = "black",alpha = .4)+
  geom_line(aes(x = Year,y = STURatio*max(WorldSupplyDemand$`EndingStocks(MMT)`),color = "Stocks-To-Use Ratio"),stat = "identity") +
  scale_y_continuous(name= "Ending Stocks (MMT)",sec.axis = sec_axis(trans = ~./max(WorldSupplyDemand$`EndingStocks(MMT)`),name = "Stocks-To-Use Ratio (%)",labels = scales::label_percent())) +
  scale_x_continuous(breaks = seq(1960,2020,10)) +
  theme_linedraw() +
  theme(legend.position = "bottom")

数据：

    structure(list(Year = c(1960,1961,1962,1963,1964,1965,1966,1967,1968,1969,1970,1971,1972,1973,1974,1975,1976,1977,1978,1979,1980,1981,1982,1983,1984,1985,1986,1987,1988,1989,1990,1991,1992,1993,1994,1995,1996,1997,1998,1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020),`EndingStocks(MMT)` = c(82.849,69.85,75.846,70.327,78.479,60.734,87.622,97.664,121.311,103.543,80.529,89.244,74.928,82.667,81.353,86.719,127.352,109.207,134.848,120.453,112.642,112.632,130.131,145.78,168.405,178.435,190.882,158.789,134.75,136.584,170.884,161.284,176.731,182.663,163.921,155.786,164.389,197.915,209.294,209.072,206.051,203.297,169.109,135.912,156.427,153.28,133.491,128.475,170.062,204.078,199.211,199.418,179.534,197.703,222.76,244.994,262.988,284.106,279.801,297.12,314.84
    ),STURatio = c(0.301557489526347,0.249384126530758,0.264261648508245,0.239068432986256,0.251835521840143,0.179621025484809,0.263788997702963,0.291137165121014,0.346212132022432,0.274209096253767,0.208611381675751,0.227974986205628,0.179854681795378,0.194878794522356,0.194543419724804,0.209379195117005,0.291057687253313,0.235920224325877,0.275164060204381,0.232741430614059,0.211017527032394,0.206519845759203,0.233969028513689,0.255487244915842,0.285466556144892,0.314575899468288,0.317676036413867,0.247207051804986,0.215788512844821,0.215196275376362,0.259567610098718,0.243269455568376,0.269013334145153,0.27830545144285,0.256095350879112,0.241592357675666,0.241881564272114,0.290602745760223,0.307599829514557,0.298202699445306,0.299927365673803,0.293608681586579,0.238451711515575,0.194882457108854,0.218073560635315,0.207311910561573,0.183357691103187,0.175121382051541,0.216001666416874,0.258023486335039,0.252623422934455,0.232926313625543,0.219384812403465,0.228728671982378,0.25617170726322,0.275743540971429,0.285296162862725,0.307339315559738,0.307886058357294,0.31757568502375,0.335068415300081)),row.names = c(NA,-61L),class = "data.frame")

解决方法

我不知道您需要STUColor用于...

除此之外。您可以通过将fill内的aes设置为您喜欢的字符串来将其添加到图例中。该字符串将在图例中用作标签。

要设置fill，您需要使用scale_fill_manual。在value参数中，指定您在[Ending Stocks]之前设置的标签等于在这种情况下选择的[stockcol]的颜色。

只需设置""相应的实验室即可删除不需要的名称。

library(dplyr)
library(ggplot2)
stockscol <- "#69b3a2"
STUColor <- rgb(0.2,0.6,0.9,1) # unused!

WorldSupplyDemand %>%
    select(Year,`EndingStocks(MMT)`,STURatio) %>%
    ggplot() +
    geom_bar (aes(x = Year,y =`EndingStocks(MMT)`,fill = "Ending Stocks"),stat = "identity",color = "black",alpha = .4)+
    geom_line(aes(x = Year,y = STURatio*max(WorldSupplyDemand$`EndingStocks(MMT)`),color = "Stocks-To-Use Ratio"),stat = "identity") +
    scale_y_continuous(name = "Ending Stocks (MMT)",sec.axis = sec_axis(trans = ~./max(WorldSupplyDemand$`EndingStocks(MMT)`),name = "Stocks-To-Use Ratio (%)",labels = scales::label_percent())) +
    scale_x_continuous(breaks = seq(1960,2020,10)) +
    scale_fill_manual(values = c("Ending Stocks" = stockscol)) +
    theme_linedraw() +
    theme(legend.position = "bottom") +
    labs(colour = "",fill = "")