R中的等值线映射问题

时间:2010-04-13 14:29:08

标签: r mapping plot

编辑:我已经意识到问题的根源。我只有我所拥有数据的县的计数信息,这比我正在策划的区域的县数少。

理所当然,问题的代码行在这里:

mapnames <- map("county",plot=FALSE)[4]$names
colorsmatched <- d$colorBuckets [na.omit(match(mapnames ,d$stcon))]

有没有人建议如何生成一个适当长度的矢量,该矢量与地图库中NY,NJ,CT和PA的县数相匹配?我想合并我拥有的计数数据,并为我没有信息的县提供零。

我正在尝试按照此处所述的教程:http://www.thisisthegreenroom.com/2009/choropleths-in-r/

以下代码执行,但它不能正确匹配我的数据集与maps_counties数据,或者它没有按照我期望的顺序绘制它。例如,较大NYC区域的结果区域没有显示密度,而PA中的随机区域显示最高密度。

我的数据表的一般格式是:

county state count
fairfield connecticut 17
hartford connecticut 6
litchfield connecticut 3
new haven connecticut 12
...
...
westchester new york 70
yates new york 1
luzerne pennsylvania 1

请注意,这些数据按州和县的顺序排列,包括CT,NJ,NY和&amp ;;的数据。 PA。

首先,我读了我的数据集:

library(maps)
library(RColorBrewer)
d <- read.table("gissum.txt", sep="\t", header=TRUE)

#Concatenate state and county info to match maps library
d$stcon <- paste(d$state, d$county, sep=",")

#Color bins
colors = brewer.pal(5, "PuBu")
d$colorBuckets <- as.factor(as.numeric(cut(d$count,c(0,10,20,30,40,50,300))))

这是我的匹配

mapnames <- map("county",plot=FALSE)[4]$names
colorsmatched <- d$colorBuckets [na.omit(match(mapnames ,d$stcon))]

绘图:

map("county"
  ,c("new york","new jersey", "connecticut", "pennsylvania")
  ,col = colors[d$colorBuckets[na.omit(match(mapnames ,d$stcon))]]
  ,fill = TRUE
  ,resolution = 0
  ,lty = 0
  ,lwd= 0.5
)
map("state"
  ,c("new york","new jersey", "connecticut", "pennsylvania")
  ,col = "black"
  ,fill=FALSE
  ,add=TRUE
  ,lty=1
  ,lwd=2
)

map("county"
   ,c("new york","new jersey", "connecticut", "pennsylvania")
   ,col = "black"
   ,fill=FALSE
   ,add=TRUE
  , lty=1
  , lwd=.5
)
title(main="Respondent Home ZIP Codes by County")

我确信我遗漏了一些基本的东西:地图功能绘制项目的顺序 - 但我似乎无法弄明白。谢谢您的帮助。如果您需要更多信息,请与我们联系。

1 个答案:

答案 0 :(得分:0)

通过将数据与选择状态的地图中的数据合并,可以找到解决问题的方法。这是你在找什么?

library(maps);
library(RColorBrewer);

# Create Dummy Data Frame to Play With

d = rbind(c('fairfield','connecticut',17),c('westchester','new york',70), c('luzerne','pennsylvania',1));
d = data.frame(d);
names(d) = c("county", "state", "count");
d$count = as.numeric(as.character(d$count));
d$stcon = paste(d$state, d$county, sep=",");

# Extract mapnames for States

mapnames2 = map("county",c("new york","new jersey", "connecticut", "pennsylvania"),plot=FALSE)[4]$names;
mapnames2 = data.frame(mapnames2);
names(mapnames2) = "stcon";

# Merge with d

d = merge(mapnames2, d, all = T);
d$count[is.na(d$count)] = 0;


# Color bins
colors = brewer.pal(5, "PuBu");
d$colorBuckets = as.factor(as.numeric(cut(d$count,c(0,10,20,30,40,50,300))));

map("county"
  ,c("new york","new jersey", "connecticut", "pennsylvania")
  ,col = colors[d$colorBuckets]
  ,fill = TRUE
  ,resolution = 0
  ,lty = 0
  ,lwd= 0.5
)
map("state"
  ,c("new york","new jersey", "connecticut", "pennsylvania")
  ,col = "black"
  ,fill=FALSE
  ,add=TRUE
  ,lty=1
  ,lwd=2
)

map("county"
   ,c("new york","new jersey", "connecticut", "pennsylvania")
   ,col = "black"
   ,fill=FALSE
   ,add=TRUE
  , lty=1
  , lwd=.5
)
title(main="Respondent Home ZIP Codes by County")