如何在ggplot中为平滑线设置alpha

rf7 发表于 Dev

射频7

我正在使用Alpha设置ggplot中平滑线的透明度，但我只在围绕拟合线的误差带中获得了透明度。

我的代码如下：

z1 <- rnorm(10)

z2 <- z1 ^ 2

error <- rnorm(10, 0.25)

y <- 1 + 0.5 * z1 + error

data1 <- data.table(y, z1, z2)

ggplot(data1) +
  geom_point(aes(x = z1, y = y), color = "blue", size = 3) +
  geom_point(aes(x = z2, y = y), color = "red", size = 3) +
  geom_smooth(method = lm, aes(x = z1, y = y), color = "blue", size = 2, alpha = 0.1) +
  geom_smooth(method = lm, aes(x = z2, y = y), color = "red", size = 2, alpha = 0.1)

输出是这样的：

我如何也可以明确设置回归线的透明度？

您的建议将不胜感激。

呼叫

您可以geom_line用于对回归线进行更细粒度的控制。

ggplot(data1) +
  geom_point(aes(x = z1, y = y), color = "blue", size = 3) +
  geom_point(aes(x = z2, y = y), color = "red", size = 3) +
  geom_line(stat = "smooth", method = lm, aes(x = z1, y = y), color = "blue", size = 2, alpha = 0.1) +
  geom_line(stat = "smooth", method = lm, aes(x = z2, y = y), color = "red", size = 2, alpha = 0.1) +
  geom_smooth(method = lm, aes(x = z1, y = y), color = NA, size = 2, alpha = 0.1) +
  geom_smooth(method = lm, aes(x = z2, y = y), color = NA, size = 2, alpha = 0.1)