How to get ternary contour plots with ggtern 2.1.0?

Question

I was experimenting with this code and I am trying to get the gridlines above the plot.

enter image description here

The code used is the same as in the OP:

#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")

Is it possible to get the gridlines above the contour?

Update

To get gridlines on the top I updated to ggtern 2.1.0. After the update I had to change stat_density2d -> stat-density_tern and geom_density2d -> geom_density_tern couple of changes to get the code working. Although it compiled the figure shown below, I cannot reproduce the previous plots shown above. And I had to add na.rm = TRUE for the code to work

library(ggtern)
#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_density_tern(geom="polygon",
                 n=400,
                 aes(fill=..level..,
                     weight=d,
                     alpha=abs(..level..)),
                 na.rm = TRUE) + 
  geom_density_tern(aes(weight=d,color=..level..),
                 n=400,
                  na.rm = TRUE) +
  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.pdf")

Why can't I get plots with the previous ggtern version with the updated version? What is binwidth replaced with?

`theme_gridsontop()` – Nicholas Hamilton Mar 18 '16 at 19:05 — Nicholas Hamilton, Mar 18 '16 at 19:05

score 2 · Accepted Answer · answered Mar 19 '16 at 22:13

There has been a number of changes since that code was put online.

Firstly, and Most noticeably, with regard to your question, is that the kernel density by default now is calculated on the inverse log-ratio space, this can be suppressed by the base='identity' argument.

Secondly, the density_tern geometry followed the same path as ggplot2, in the use if the 'h' argument, as such, binwidth now has no meaning.

Here is an example, which renders a result closer to your initial expectation:

#Build Plot
ggtern(data=df,aes(x=c,y=a,z=b),aes(x,y,z)) + 
  stat_density_tern(geom="polygon",color='black',
                    n=400,h=0.75,expand = 1.1,
                    base='identity',
                    aes(fill   = ..level..,weight = d),
                    na.rm = TRUE) + 
  geom_point(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_rgbw() + 
  theme(legend.justification=c(0,1), legend.position=c(0,1)) +
  theme_gridsontop() + 
  guides(fill = guide_colorbar(order=1),color="none") + 
  labs(  title= "Ternary Plot and Filled Contour",fill = "Value, V")

How to get ternary contour plots with ggtern 2.1.0?

1 Answers1