三元图和填充轮廓-ggtern

Question

我正在尝试使用ggtern库创建一个三元轮廓填充图。 使用的代码是

a <- c(0.50, 0.625, 0.375, 0.25, 0.5625, 0.125, 0.25, 0.3125, 0.375, 0.4375, 0.1875, 0.3125, 0.375, 0.4375)
b <- c(0.25, 0.1875, 0.3125, 0.375, 0.25, 0.4375, 0.25, 0.375, 0.375, 0.4375, 0.875, 0.3125, 0.25, 0.125)
c <- c(0.25, 0.1875, 0.3125, 0.375, 0.1875, 0.4375, 0.50, 0.3125, 0.25, 0.125, 0.625, 0.375, 0.375, 0.4375) 
d <- c(77.82325, 74.59318767, 76.76495015, 76.62122282, 77.95608657, 76.91320817, 68.50986659,8.53724416,80.32237597, 85.43315399, 61.80292426, 74.71471485, 73.27176908, 67.51782848)
df <- data.frame(a, b, c, d)

df$id <- 1:nrow(df)

#Build Plot
ggtern(data = df,aes(x = c,y = a,z = b)) +
stat_density2d(geom = "polygon", n = 400, aes(fill = ..level.., weight = d, alpha = abs(..level..))) +
geom_density_tern(aes(weight = d,color = ..level..), n = 400) +
geom_point(aes(fill = d),color = "black",size = 5,shape = 21) +
geom_text(aes(label = id),size = 3) +
labs(x = "X (%)",y = "Y (%)",z = "Z (%)",title = "Title", size = 3) +
scale_fill_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
scale_color_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
theme_custom(base_size = 12, base_family = "", col.T = "black", col.L = "black", col.R = "black", col.BG = "white") +
tern_anticlockwise() +
tern_limits(breaks = seq(0.1,1,by = 0.1)) + #AFFECT ALL SCALES
theme(axis.tern.arrowstart = 0.4,axis.tern.arrowfinish = 0.6) +
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 filled contour plot", fill = "Value, V",alpha = "|V - 0|")

但是我收到以下警告消息：

Error: coord_tern requires the following missing aesthetics: z

为什么会发生此错误，以及如何解决？ 请帮忙

Answer 1

@jhoward，感谢您对问题的解释。

我还想在ggtern的最新版本中演示一些其他功能。 请参见下面的插值几何，以进行曲面建模：

ggtern(data = df,aes(x = c,y = a, z = b)) + 
  geom_interpolate_tern(aes(value=d,colour=..level..),bins=50) +
  geom_point(aes(color=d),size=10) + 
  geom_text(aes(label=round(d,0)),size=3) + 
  theme_bw() + 
  theme(legend.position=c(0,1),
        legend.justification=c(0,1)) + 
  scale_colour_gradient(low='green',high='red') + 
  labs( title = "Ternary filled contour plot", colour = "Value, V")

产生以下输出：

Answer 2

当发生这种情况时，显而易见的方法是对代码进行解构，以查看错误的确切位置。 如果这样做，您将知道它正在调用stat_density2d(...) 。 我ggtern无法使ggtern版本的stat_density2d(...)正常工作（尽管我很想看看别人做的例子）。

如果删除该调用，并将fill=..level..美化到geom_density_tern(...) ，则会得到以下信息：

library(ggtern)
ggtern(data = df,aes(x = c,y = a, z = b)) +
  geom_density_tern(aes(fill=..level..),n = 400) +
  geom_point(aes(fill = d),color = "black",size = 5,shape = 21) +
  geom_text(aes(label = id),size = 3) +
  labs(x = "X (%)",y = "Y (%)",z = "Z (%)",title = "Title", size = 3) +
  scale_fill_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
  scale_color_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
  theme_custom(base_size = 12, base_family = "", col.T = "black", col.L = "black", col.R = "black", col.BG = "white") +
  tern_anticlockwise() +
  tern_limits(breaks = seq(0.1,1,by = 0.1)) + #AFFECT ALL SCALES
  theme(axis.tern.arrowstart = 0.4,axis.tern.arrowfinish = 0.6) +
  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 filled contour plot", fill = "Value, V",alpha = "|V - 0|")

注意轮廓填充是如何全黄的。 发生这种情况的原因是，您试图将fill用于两种不同的事物：z级别（来自b列）和点，其中fill来自d列。 ggplot （扩展名为gggtern ）创建单个填充比例。 由于df$b大约在（0.1，1）范围内，而df$d大约在（60,90）范围内，因此轮廓填充水平全部在该范围的低端，因此为黄色。

如果您确实希望轮廓填充和点使用不同的调色板，则可以对点使用颜色美感：

library(ggtern)
ggtern(data = df,aes(x = c,y = a, z = b)) +
  geom_density_tern(aes(fill=..level..),n = 400) +
  geom_point(aes(color = d),size = 8,shape = 20) +
  geom_text(aes(label = id),size = 3) +
  labs(x = "X (%)",y = "Y (%)",z = "Z (%)",title = "Title", size = 3) +
  scale_fill_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
  scale_color_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
  theme_custom(base_size = 12, base_family = "", col.T = "black", col.L = "black", col.R = "black", col.BG = "white") +
  tern_anticlockwise() +
  tern_limits(breaks = seq(0.1,1,by = 0.1)) + #AFFECT ALL SCALES
  theme(axis.tern.arrowstart = 0.4,axis.tern.arrowfinish = 0.6) +
  theme(legend.justification = c(0,1), legend.position = c(0,1)) +
  guides(fill = guide_colorbar(order = 2), color = guide_colorbar(order = 1)) +
  labs( title = "Ternary filled contour plot", color = "Value, V", fill = "|V - 0|")

编辑：根据OP的评论添加。

ggtern(data = df,aes(x = c,y = a, z = b)) +
  geom_density_tern(aes(fill=..level..),n = 400) +
  geom_point(aes(color = d),size = 8,shape = 20) +
  geom_text(aes(label = id),size = 3) +
  labs(x = "X (%)",y = "Y (%)",z = "Z (%)",title = "Title", size = 3) +
  scale_fill_gradient2(low = "green", mid = "yellow", high = "red", midpoint = 10) +
  scale_color_gradient2(low = "green", mid = "yellow", high = "red", limits=c(60,90),midpoint = 75) +
  theme_custom(base_size = 12, base_family = "", col.T = "black", col.L = "black", col.R = "black", col.BG = "white") +
  tern_anticlockwise() +
  tern_limits(breaks = seq(0.1,1,by = 0.1)) + #AFFECT ALL SCALES
  theme(axis.tern.arrowstart = 0.4,axis.tern.arrowfinish = 0.6) +
  theme(legend.justification = c(0,1), legend.position = c(0,1)) +
  guides(fill = guide_colorbar(order = 2), color = guide_colorbar(order = 1)) +
  labs( title = "Ternary filled contour plot", color = "Value, V", fill = "|V - 0|")