r - 使用 R 中的州缩写和特征频率创建美国的热图

Question

我想创建一张美国 map (可能是热图)来显示各州之间某个特征的频率。我不确定要使用什么包，或者我的数据格式是否正确。我的数据在表中 tf

tf
 AB  AK  AL  AN  AR  AZ  CA  CO  CT  DC  DE  EN  FL  GA  HI  IA  ID  IL  IN  KS 
  1  21  31   1  12  56 316  53  31  16   7   1 335  63  11  42  29  73  40  2

在大多数情况下，我的缩写是美国(除了少数加拿大实例)。在 map 上以图形方式显示它的最佳建议方法是什么？

现在如何获得每种颜色小于 50 的粒度？

Answer 1

两个包:
map ，ggplot2。
有一个很好的例子:
?map_data()

只是开始:

tf= structure(list(state = structure(1:14, .Label = c("AK", "AL", 
"AR", "AZ", "CA", "CO", "CT", "DE", "FL", "GA", "IA", "IL", "IN", 
"KS"), class = "factor"), num = c(21L, 31L, 12L, 56L, 316L, 53L, 
31L, 7L, 335L, 63L, 42L, 73L, 40L, 2L), region = structure(c(2L, 
1L, 4L, 3L, 5L, 6L, 7L, 8L, 9L, 10L, 13L, 11L, 12L, 14L), .Label = c("alabama", 
"alaska", "arizona", "arkansas", "california", "colorado", "connecticut", 
"delaware", "florida", "georgia", "illinois", "indiana", "iowa", 
"kansas"), class = "factor")), .Names = c("state", "num", "region"
), class = "data.frame", row.names = c(NA, -14L))

require(maps);require(ggplot2)

states <- map_data("state")
tfmerged <- merge(states, tf, sort = FALSE, by = "region")
tfmerged <- tfmerged[order(tfmerged$order), ]
qplot(long, lat, data = tfmerged, group = group, fill = num,
geom="polygon")

然后填写其余的状态信息。