Show different geoms in a legend for a common aesthetic-CodePudding

This graph uses points, pointranges, and lines to plot different kinds of data. The data sources are distinguished by color.

Currently, the legend shows all the geoms at once.

I would like the legend to reflect only the geom used with that color. So:

"acs 1-year" will only show a pointrange
"admin v1" and "admin v2" will only show a line
"decennial census" will only show a point

I want to keep all four legend entries in a single legend for the "colour" aesthetic.

Here is the replication data.

df <- structure(list(year = c(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, 2021, 2022), admin1 = c(105939L, 105568L, 105207L, 
105252L, 104878L, 104498L, 103960L, 104071L, 103689L, 103474L, 
104039L, 104874L, 104949L, 105767L, 106559L, 107339L, 106348L, 
105580L, 104455L, 102815L, 101121L, 99244L, 96823L, 95091L, 94082L, 
92769L, 91811L, 91680L, 91350L, 82767L, 89030L, 89764L, 89942L
), admin2 = c(105944L, 105573L, 105209L, 105254L, 104880L, 104500L, 
103961L, 104072L, 103691L, 103475L, 104039L, 104874L, 104949L, 
105767L, 106559L, 107339L, 106348L, 106021L, 104874L, 103208L, 
101580L, 99732L, 97343L, 95648L, 94685L, 93390L, 92467L, 92375L, 
92137L, 92703L, 93417L, 94222L, 95200L), decennial_count = c(107682, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, 105235, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, 100296, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA), acs1 = c(NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, 113122, 109275, 105005, 105918, 104330, 102660, 
98506, 95432, 97196, 97841, 94046, 93184, 92218, 96609, 92982, 
NA, 96044, NA), acs1_moe = c(NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, 4433, 3735, 3484, 3227, 3379, 3527, 
3171, 3259, 3105, 3800, 3711, 3232, 3507, 3816, 3261, NA, 3817, 
NA)), row.names = c(NA, -33L), class = c("tbl_df", "tbl", "data.frame"
))

And here is the minimal ggplot2 code.

ggplot(df)  
  geom_line(aes(x = year, y = admin1, color = "admin v1"))  
  geom_line(aes(x = year, y = admin2, color = "admin v2"))  
  geom_pointrange(aes(x = year, y = acs1, ymin = (acs1 - acs1_moe),
                      ymax = (acs1   acs1_moe), color = "acs 1-year"))  
  geom_point(aes(year, decennial_count, color = "decennial census"),
             size = 4, shape = "diamond")

CodePudding user response：

If you want the legend keys all grouped under the color aesthetic but different shapes for each one, you will need to override the guide aesthetics manually

ggplot(df)  
  geom_line(aes(x = year, y = admin1, color = "admin v1"))  
  geom_line(aes(x = year, y = admin2, color = "admin v2"))  
  geom_pointrange(aes(x = year, y = acs1, ymin = (acs1 - acs1_moe),
                      ymax = (acs1   acs1_moe), color = "acs 1-year"),
                  key_glyph = draw_key_blank)  
  geom_point(aes(year, decennial_count, color = "decennial census"),
             size = 4, shape = "diamond")  
  guides(colour = guide_legend(override.aes = list(linetype = c(1, 1, 1, 0),
                                                   shape = c(16, NA, NA, 18),
                                                   size = c(3, 1, 1, 4))))