How to add gradient color to line plot based on its corresponding y value using ggplot-CodePudding

I have a dataset that includes values for each day. I showed the sample data below:

structure(list(Global = c(-0.64, -0.52, -0.57, -0.59, -0.62, 
-0.64, -0.62, -0.58, -0.54, -0.6, -0.68, -0.68, -0.66, -0.63, 
-0.56, -0.51, -0.55, -0.61, -0.68, -0.67, -0.64, -0.57, -0.53, 
-0.62, -0.66, -0.68, -0.66, -0.63, -0.54, -0.49, -0.37, -0.66, 
-0.65, -0.61, -0.57, -0.49, -0.47, -0.67, -0.61, -0.63, -0.59, 
-0.6, -0.62, -0.45, -0.24, -0.53, -0.58, -0.58, -0.59, -0.49, 
-0.4, -0.43, -0.55, -0.53, -0.47, -0.47, -0.39, -0.34, -0.38, 
-0.49, -0.49, -0.46, -0.47, -0.39, -0.34, -0.34, -0.5, -0.51, 
-0.49, -0.43, -0.36, -0.32, -0.35, -0.44, -0.44, -0.37, -0.39, 
-0.3, -0.27, -0.27, -0.41, -0.43, -0.43, -0.38, -0.29, -0.28, 
-0.3, -0.29, -0.31, -0.33, -0.28, -0.27, -0.33, -0.14, -0.3, 
-0.34, -0.32, -0.29, -0.29, -0.27)), row.names = c(NA, -100L), class = c("tbl_df", 
"tbl", "data.frame"))

What I want to do is plot this graph such that the color of the line graph would change based on corresponding y value. This is what I have so far:

ggplot(data, aes(x=Date, y=new_global))  
  geom_line()   
  xlab("") 
  scale_x_date(date_labels = "%Y %b %d"

which results in:

and what I want to have is something like this:

As you can see, the values are in red when they are close to minimum while they are changing to green when the graph get closer to maximum value.

CodePudding user response：

ggforce package includes geoms that can have interpolated aesthetics, like a gradient:

df %>%
  mutate(row = row_number()) %>%
  ggplot(aes(row, Global, color = Global))  
  ggforce::geom_link2()   
  scale_color_gradient(low = "red", high = "white")  
  theme_dark()