如何使用ggplot更改圖例文本標簽？

Question

我想更改由紅色和藍色點表示的值的標簽。

#Number and names of variables

[1] "Date"                         "AOD_500nm"                    
"Fine_Mode_AOD_500nm.tau_f."   "Coarse_Mode_AOD_500nm.tau_c."




#create the plot

ggplot(data4, aes(x = AOD_500nm)) +
geom_point(aes(y = Fine_Mode_AOD_500nm.tau_f., colour = 
"Fine_Mode_AOD_500nm.tau_f.")) +
geom_point(aes(y = Coarse_Mode_AOD_500nm.tau_c., colour = 
"Coarse_Mode_AOD_500nm.tau_c.")) +
labs(x = "AERONET AOD (500nm)", y = "SDA AOD (500nm)", colour = "Mode" ) +
scale_colour_manual(values = c("red", "blue")) +
scale_fill_discrete(labels = c("Coarse", "Fine")) +
theme(legend.position=c(0.9, 0.9)) +
theme(axis.text.x=element_text(size = 10,hjust=1)) +
theme(axis.text.y=element_text(size = 10)) +
theme(axis.title.x = element_text(size = 12)) +
theme(axis.title.y = element_text(size = 12))

Answer 1

您可以單獨在scale_colour_manual添加標簽，而不必單獨進行scale_fill_discrete調用，如下所示：

scale_colour_manual(values = c("red", "blue"), labels = c("Coarse", "Fine"))

這是因為您要對點分別進行colour ，而不是更改fill值。