带有分箱颜色和图例的纽约州县地图

Question

我正在尝试制作纽约州的县级地图。我想根据每个县的工会化程度来为其着色。我需要地图和图例具有四种离散的红色，而不是红色渐变。我需要图例来显示这四种不同的颜色以及不重叠的标签/范围（例如 0-25；26-50；51-75；76-100）。

这是我的数据：

    fips unionized
1  36001  33.33333
2  36005  86.11111
3  36007   0.00000
4  36017   0.00000
5  36021   0.00000
6  36027  66.66667
7  36029  40.00000
8  36035  50.00000
9  36039   0.00000
10 36047  82.85714
11 36051   0.00000
12 36053 100.00000
13 36055  30.76923
14 36057   0.00000
15 36059  84.37500
16 36061  81.81818
17 36063  60.00000
18 36065  50.00000
19 36067  71.42857
20 36069   0.00000
21 36071  55.55556
22 36073   0.00000
23 36079 100.00000
24 36081  92.15686
25 36083  50.00000
26 36085 100.00000
27 36087  87.50000
28 36101   0.00000
29 36103  63.88889
30 36105   0.00000
31 36107   0.00000
32 36111  50.00000
33 36113  50.00000
34 36115 100.00000
35 36117   0.00000
36 36119  73.33333
37 36121   0.00000
38 36123   0.00000

我已经成功制作了具有颜色渐变的地图，但无法弄清楚如何在地图和图例中制作离散颜色。

这是我的代码：

library(usmap)
library(ggplot2)
plot_usmap(regions = "counties", include = c("NY"), data = Z, values = "unionized") +
  labs(title = "Percent Unionized", subtitle = "") + 
  scale_fill_continuous(low = "white", high = "red", na.value="light grey", name = "Unionization") + theme(legend.position = "right")

谢谢！

Answer 1

这可以通过

scale_fill_binned

和

guide_bins

来实现。试试这个：

library(usmap)
library(ggplot2)
plot_usmap(regions = "counties", include = c("NY"), data = Z, values = "unionized") +
  labs(title = "Percent Unionized", subtitle = "") + 
  scale_fill_binned(low = "white", high = "red", na.value="light grey", name = "Unionization", guide = guide_bins(axis = FALSE, show.limits = TRUE)) + 
  theme(legend.position = "right")

第二个选项是手动对变量进行分类，并使用

scale_fill_manual

设置填充颜色，这样可以轻松设置标签，并且具有自动添加 NA 的优点。对于色标，我使用

colorRampPalette

（默认情况下

colorRampPalette

在 RGB 颜色空间中进行插值。要获得像使用

scale_fill_binned

那样的填充颜色，您可以添加参数

space = "Lab"

。）。

library(usmap)
library(ggplot2)

Z$union_bin <- cut_interval(Z$unionized, n = 4, labels = c("0-25", "26-50", "51-75", "76-100"))

plot_usmap(regions = "counties", include = c("NY"), data = Z, values = "union_bin") +
  labs(title = "Percent Unionized", subtitle = "") + 
  scale_fill_manual(values = colorRampPalette(c("white", "red"))(5)[2:5],
                    na.value="light grey", name = "Unionization") +
  theme(legend.position = "right")

数据

Z <- structure(list(fips = c(
  36001L, 36005L, 36007L, 36017L, 36021L,
  36027L, 36029L, 36035L, 36039L, 36047L, 36051L, 36053L, 36055L,
  36057L, 36059L, 36061L, 36063L, 36065L, 36067L, 36069L, 36071L,
  36073L, 36079L, 36081L, 36083L, 36085L, 36087L, 36101L, 36103L,
  36105L, 36107L, 36111L, 36113L, 36115L, 36117L, 36119L, 36121L,
  36123L
), unionized = c(
  33.33333, 86.11111, 0, 0, 0, 66.66667,
  40, 50, 0, 82.85714, 0, 100, 30.76923, 0, 84.375, 81.81818, 60,
  50, 71.42857, 0, 55.55556, 0, 100, 92.15686, 50, 100, 87.5, 0,
  63.88889, 0, 0, 50, 50, 100, 0, 73.33333, 0, 0
)), class = "data.frame", row.names = c(
  "1",
  "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13",
  "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24",
  "25", "26", "27", "28", "29", "30", "31", "32", "33", "34", "35",
  "36", "37", "38"
))