问题
I have the following data frame:
expected observed group
1: 0.5371429 0.0000 1
2: 1.3428571 1.3736 1
3: 2.6857143 2.4554 1
4: 5.3714286 3.6403 1
5: 0.5294118 0.0000 2
6: 1.3235294 1.1494 2
7: 2.6470588 1.1364 2
8: 5.2941176 4.9774 2
9: 0.5201207 0.0000 3
10: 1.3003018 1.4327 3
11: 2.6006036 2.5918 3
12: 5.2012072 8.0769 3
13: 0.5155039 1.4851 4
14: 1.2887597 1.0638 4
15: 2.5775194 3.1700 4
16: 5.1550388 6.2500 4
17: 0.4976959 0.0000 5
18: 1.2442396 1.2384 5
19: 2.4884793 3.1073 5
20: 4.9769585 4.8148 5
I would like to scatter plot each dataset according to group, so I have the following code:
sp <- ggplot(new_df, aes(x = expected, y = observed, colour = group)) + geom_point()
sp + scale_color_gradientn(colours = rainbow(5))
and receive the below plot:
My question is how to add a linear line (intercept = 0,0) to each of the different groups? meaning, that in the end, I'll have 5 linear lines in different colors representing each group on the same plot.
And, is there a way to show the equation for each line in a legend?
回答1:
You can get the linear lines and equation/R2 text with geom_smooth
from ggplot2
and stat_poly_eq
from ggpmisc package
dat <- "expected observed group
0.5371429 0 1
1.3428571 1.3736 1
2.6857143 2.4554 1
5.3714286 3.6403 1
0.5294118 0 2
1.3235294 1.1494 2
2.6470588 1.1364 2
5.2941176 4.9774 2
0.5201207 0 3
1.3003018 1.4327 3
2.6006036 2.5918 3
5.2012072 8.0769 3
0.5155039 1.4851 4
1.2887597 1.0638 4
2.5775194 3.17 4
5.1550388 6.25 4
0.4976959 0 5
1.2442396 1.2384 5
2.4884793 3.1073 5
4.9769585 4.8148 5
"
library(ggplot2)
library(ggpmisc)
df <- read.table(text = dat, header = TRUE)
df$group <- factor(df$group)
formula <- y ~ x # needed for ggpmisc's equation and R2 text
# Put equation & R2 coef to the top left corner
ggplot(df, aes(expected, observed, colour = group)) +
geom_point(size = 2, alpha = 0.3) +
geom_smooth(method = "lm", formula = formula, se = FALSE) +
stat_poly_eq(aes(label = paste(..eq.label.., ..rr.label.., sep = "~~~~")),
label.x.npc = "left", label.y.npc = "top",
formula = formula, parse = TRUE, size = 4) +
scale_color_brewer(palette = "Dark2") +
theme_bw(base_size = 16)
来源:https://stackoverflow.com/questions/48912224/how-to-add-linear-lines-to-a-plot-with-multiple-data-sets-of-a-data-frame