R语言可视化——数据地图离散百分比填充（环渤海）

今天跟大家分享如何以百分比形式填充离散分段数据地图。

案例用环渤海三省二市的地理数据。

library(ggplot2)

library(maptools)

library(plyr)

数据导入、转换、抽取

CHN_adm2 <- readShapePoly("c:/rstudy/CHN_adm/CHN_adm2.shp")

CHN_adm2_1 <- fortify(CHN_adm2)

data1 <- CHN_adm2@data

data2 <- data.frame(id=row.names(data1),data1)

china_map_data <- join(CHN_adm2_1, data2, type = "full")

huanbohai <-subset(china_map_data,NAME_1==c("Beijing","Tianjin","Nei Mongol","Hebei","Shandong"))

建立业务数据：

huanbohai_perm<-data.frame(NAME_2=unique(huanbohai$NAME_2),zhibiao=rnorm(42,100,50))

huanbohai_perm$zhibiao<-round(huanbohai_perm$zhibiao,0)

write.table (huanbohai_perm, file ="C:/rstudy/huanbohai.csv", sep =",", row.names =FALSE)

业务数据导入及合并：

mydata<-read.csv("C:/rstudy/huanbohai.csv",header=T)

huanbohai_map_data <- join(huanbohai,mydata, type="full")

###将转换的分段因子变量重新命名为我们需要的分段阀值：

huanbohai_map_data$fau <- cut(huanbohai_map_data$zhibiao, breaks = c(0,40,80,120,160,200))

huanbohai_map_data$fam<-factor(huanbohai_map_data$fau,levels=c('(0,40]','(40,80]','(80,120]','(120,160]','(160,200]'),labels=c('0~40','40~80','80~120','120~160','160~200'),order=TRUE)

离散颜色标度填充（实际值分段）

windowsFonts(myFont = windowsFont("微软雅黑"))

ggplot(huanbohai_map_data, aes(x = long, y = lat, group = group,fill =fam)) +

geom_polygon(colour="white")+

scale_fill_brewer(palette="Greens") + ###Blues&Greens

coord_map("polyconic") +

ggtitle("某公司2015~2016年度营业状况分布图")+

guides(fill=guide_legend(reverse=TRUE,title=NULL))+

theme(

title=element_text(family="myFont"),

legend.text.align=1, ###图例标签右对齐

panel.grid = element_blank(),

panel.background = element_blank(),

axis.text = element_blank(),

axis.ticks = element_blank(),

axis.title = element_blank(),

legend.position = c(0.08,0.6)

)

以上是昨天在东三省填充地图中所使用过的方法，接下来我解释一种新的填充方案，通过将数量段转换为百分比进行离散颜色标度填充：

离散颜色标度分割（百分比数量段）：

qa <- quantile(na.omit(huanbohai_map_data$zhibiao), c(0,0.2,0.4,0.6,0.8,1.0))

huanbohai_map_data$zhibiao_q<-cut(huanbohai_map_data$zhibiao,qa,labels = c("0-20%", "20-40%","40-60%","60-80%", "80-100%"),include.lowest = TRUE)

> levels(huanbohai_map_data$zhibiao_q)

[1] "0-20%" "20-40%" "40-60%" "60-80%" "80-100%"

通过将指标变量以分段百分比的方式进行分割，新建立一个百分比分段因子变量：

离散渐变（百分比）

windowsFonts(myFont = windowsFont("微软雅黑"))

ggplot(huanbohai_map_data,aes(long,lat))+

geom_polygon(aes(group=group,fill=zhibiao_q),colour="white")+

scale_fill_brewer(palette="Greens")+

coord_map("polyconic") +

guides(fill=guide_legend(reverse=TRUE,title=NULL))+

ggtitle("某公司2015~2016年度营业状况分布图")+

theme(

title=element_text(family="myFont"),

panel.grid = element_blank(),

panel.background = element_blank(),

axis.text = element_blank(),

axis.ticks = element_blank(),

axis.title = element_blank(),

legend.position =c(0.2,0.7),

legend.text.align=1

)

###带标签

接下来处理标签问题：

创建各城市中心地理坐标：

midpos <- function(data1) mean(range(data1,na.rm=TRUE))

centres <- ddply(huanbohai_map_data,.(city),colwise(midpos,.(long,lat)))

填充并添加标签：

ggplot(huanbohai_map_data,aes(long,lat))+

geom_polygon(aes(group=group,fill=zhibiao_q),colour="white")+

scale_fill_brewer(palette="Greens")+

coord_map("polyconic") +

geom_text(aes(label=city),size =3,family="myFont",fontface="plain",data=centres) +

guides(fill=guide_legend(reverse=TRUE,title=NULL))+

ggtitle("某公司2015~2016年度营业状况分布图")+

theme(

title=element_text(family="myFont"),

title=element_text(family="myFont"),

panel.grid = element_blank(),

panel.background = element_blank(),

legend.text.align=1,

axis.text = element_blank(),

axis.ticks = element_blank(),

axis.title = element_blank(),

legend.position = c(0.2,0.7)

)