Ternary plot and filled contour

Question

Users, I'd like to have some tips for a ternaryplot ("vcd").

I have this dataframe:

a <- c(0.1, 0.5, 0.5, 0.6, 0.2, 0, 0, 0.004166667, 0.45) 
b <- c(0.75,0.5,0,0.1,0.2,0.951612903,0.918103448,0.7875,0.45)
c <- c(0.15,0,0.5,0.3,0.6,0.048387097,0.081896552,0.208333333,0.1) 
d <- c(500,2324.90,2551.44,1244.50, 551.22,-644.20,-377.17,-100, 2493.04) 
df <- data.frame(a, b, c, d)

and I'm building a ternary plot:

ternaryplot(df[,1:3], df$d)

How can I map the continuous variable d, obtaining a result similar to this one?

Answer 1

I needed to solve a similar problem, which was partially the catalyst for writing a package as an extension to ggplot2, for ternary diagrams. The package is available on CRAN.

The Output for this Problem:

Code to Build the Above

#Orignal Data as per Question
a <- c(0.1, 0.5,0.5, 0.6, 0.2, 0          , 0         , 0.004166667, 0.45) 
b <- c(0.75,0.5,0  , 0.1, 0.2, 0.951612903,0.918103448, 0.7875     , 0.45)
c <- c(0.15,0  ,0.5, 0.3, 0.6, 0.048387097,0.081896552, 0.208333333, 0.10) 
d <- c(500,2324.90,2551.44,1244.50, 551.22,-644.20,-377.17,-100, 2493.04) 
df <- data.frame(a, b, c, d)

#For labelling each point.
df$id <- 1:nrow(df)

#Build Plot
ggtern(data=df,aes(x=c,y=a,z=b),aes(x,y,z)) + 
  stat_density2d(geom="polygon",
                 n=400,
                 aes(fill=..level..,
                 weight=d,
                 alpha=abs(..level..)),
                 binwidth=100) + 
  geom_density2d(aes(weight=d,color=..level..),
                 n=400,
                 binwidth=100) +
  geom_point(aes(fill=d),color="black",size=5,shape=21) + 
  geom_text(aes(label=id),size=3) + 
  scale_fill_gradient(low="yellow",high="red") + 
  scale_color_gradient(low="yellow",high="red") + 
  theme_tern_rgbw() + 
  theme(legend.justification=c(0,1), legend.position=c(0,1)) + 
  guides(fill = guide_colorbar(order=1),
         alpha= guide_legend(order=2),
         color="none") + 
  labs(  title= "Ternary Plot and Filled Contour",
         fill = "Value, V",alpha="|V - 0|")

#Save Plot
ggsave("TernFilled.png")