如何操作tmap图例？

Question

我正在创建一张鸟类物种每年百分比变化的专题地图。下面是我的代码：

tm_shape(grid83)+
  tm_fill("trend", title = "Percent change per Year", textNA = "None counted", style="fixed",
    breaks=c(-Inf, -1.5, -0.25, 0.25, 1.5, Inf),
    palette = c("red", "orange", "yellow", "turquoise", "blue", "white"))+
  tm_borders(NA)+
tm_shape(uscan83)+ # add US and CAN 
  tm_borders()+
tm_layout(
  "Western Grebe",
  legend.title.size=1,
  legend.text.size = 0.6,
  legend.position = c("left","bottom"),
  legend.bg.color = "white",
  legend.digits = 5,
  legend.bg.alpha = 1)

当前，所有NA值都显示为灰色。我试着改变了调色板：

palette = c("red", "orange", "yellow", "turquoise", "blue", "white"))

但这似乎不起作用。NA值仍为灰色。我做错了什么？

非常感谢！

Answer 1

因此，您正在尝试更改特定于NA值的颜色？tm_fill()的colorNA参数就是为了达到这个目的。

下面是一个例子：

library(tmap)
data(Europe)
tm_shape(Europe) +
tm_fill("gdp_cap_est", title = "GDP", style = "fixed",
        breaks = c(0, 10000, 20000, 30000, 40000, Inf),
        textNA = "Dunno", 
        colorNA = "green",   # <-------- color for NA values
        palette = c("red", "orange", "yellow", "turquoise", "blue", "white")) +
tm_borders() +
tm_layout("Wealth (or so)",
          legend.title.size = 1,
          legend.text.size = 0.6,
          legend.position = c("left","bottom"),
          legend.bg.color = "white",
          legend.digits = 5,
          legend.bg.alpha = 1)

它看起来是这样的：

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