根据条形大小更改条形颜色 R

Question

使用 ggplot 我已经制作了一个带有一些值的直方图。 我想更改最高条的颜色，以使 plot 更清晰。

library(ggplot2)
ggplot(df, 
       aes(as.Date(created_at), as.numeric(count))) +
  geom_col(fill = 'cornflowerblue') + 
  theme_minimal(base_size = 10) +
  xlab(NULL) + ylab(NULL) + 
  scale_x_date(date_labels = "%Y/%m/%d",date_breaks = "days",expand = c(0,0)) +  #El espaciado por días
  theme(axis.text.x=element_text(angle=90, vjust = 0.5))+#Cambiamos la posición del x 
  geom_text(aes(label = count, y = count+50), position = position_dodge(0.9),angle=90, vjust = 0.5,size=3)+
  ggplot2::theme(
    plot.title = ggplot2::element_text(face = "bold",colour = "black"))+
  ggplot2::labs(
    x = NULL, y = NULL, #Info en cada eje 
    title = "Tweets sobre el COVID-19 por día", #Texto 
    subtitle = ""
  )

Answer 1

这可能会帮助您：

library(ggplot2)
library(dplyr)

data(mtcars)

count(mtcars, cyl) %>%
  mutate(col=ifelse(n==max(n), "red","blue")) %>%  # Add this line,
  ggplot(aes(cyl, n, fill=as.factor(col))) +
    geom_col() +
    ylab("Frequency") +
    scale_fill_identity() +  # And this one to use the actual colours.
    theme_minimal()

Answer 2

我试过这个，但不起作用

covidtweets %>% 
  mutate(col=ifelse(count==max(count), "red","blue")) %>%
ggplot( aes(as.Date(created_at), as.numeric(count),fill=as.factor(col))) +
  theme_minimal(base_size = 10) +
  #geom_line(data = spain_deaths, aes(as.Date(time), as.numeric(cum_dead)), color= 'blue4', size=1.1)+
 #geom_point(color="red")+
  xlab(NULL) + ylab(NULL) + 
  scale_x_date(date_labels = "%Y/%m/%d",date_breaks = "days",expand = c(0,0)) +  #El espaciado por días
  theme(axis.text.x=element_text(angle=90, vjust = 0.5))+#Cambiamos la posición del x 
  geom_text(aes(label = count, y = count+50), position = position_dodge(0.9),angle=90, vjust = 0.5,size=3)+
  ggplot2::theme(
    plot.title = ggplot2::element_text(face = "bold",colour = "black"))+
  ggplot2::labs(
    x = NULL, y = NULL, #Info en cada eje 
    title = "Tweets sobre el COVID-19 por día", #Texto 
    subtitle = ""
  )