如何使用 ggplot 在美国各州地图中有条件地着色？

Question

我的目标是将低于销售平均值的州显示为红色，将高于销售平均值的州显示为绿色。我的代码似乎只是在做某种颜色轮廓，我不知道蓝色填充是从哪里来的。实际数据有所有状态，但我只是为了这个目的做了5个例子。

    library(ggplot2)
    library(tidyverse)
    library(mapdata)
    library(dplyr)
    
    MainStates <- map_data("state")
    State_Name <- c("alabama","arkansas","arizona","california","colorado")
    Sales <- c(100,200,250,275,310)
    df2 <- data.frame(State_Name,Sales)
    MergedStates <- inner_join(MainStates, df2, by = c("region" = "State_Name"))

    p <- ggplot() + geom_polygon(data = MergedStates,
                         aes(x=long, y=lat, group=group, fill=Sales),
                         color = ifelse(MergedStates$Sales <= 
                         mean(MergedStates$Sales),"red","green"), size = 0.2)
    p

Answer 1

我想这就是你想要达到的目的吧？在 geom_sf 中，颜色是指边框的颜色，fill 是指填充多边形的颜色（对于多边形）。

library(ggplot2)
library(tidyverse)
library(mapdata)
#> Loading required package: maps
#> 
#> Attaching package: 'maps'
#> The following object is masked from 'package:purrr':
#> 
#>     map
library(dplyr)

MainStates <- map_data("state")
State_Name <- c("alabama","arkansas","arizona","california","colorado")
Sales <- c(100,200,250,275,310)
df2 <- data.frame(State_Name,Sales)
MergedStates <- inner_join(MainStates, df2, by = c("region" = "State_Name"))

p <- ggplot() + geom_polygon(data = MergedStates,
                             aes(x=long, y=lat, group=group),
                             fill = ifelse(MergedStates$Sales <= 
                                              mean(MergedStates$Sales),"red","green"), size = 0.2)
p

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于 2021 年 10 月 1 日创建

如何使用 ggplot 在美国各州地图中有条件地着色？

How do I conditionally color in a US States map using ggplot?

r

ggplot2

maps

tidyverse