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)
)
