子设置形状文件以绘制区域并解决 ggplot 和数据中的不匹配问题

Question

我正在用数据（个案）绘制印度的地区地图。首先，我读取每个地区和地区形状文件的数据。后来我合并了两个上区。使用强化数据我得到了 ggplot。我使用 ggplot 得到了一个漂亮的情节。

##nr1 <- read.csv("../OUTPUT/working_districts_state.csv")
## Creating data frame
DISTRICT <- c("Alappuzha","Ernakulam","Idukki","Kannur","Kasaragod","Kollam","Kottayam","Kozhikode","Malappuram","Palakkad","Pathanamthitta","Thiruvananthapuram","Thrissur","Wayanad")
ST_NM <- rep("Kerala",length(DISTRICT))
reg.cases <- sample(0:250,length(DISTRICT), replace=T)
nr1 <- data.frame(DISTRICT, ST_NM, reg.cases)

india.dist <- readShapeSpatial("./shapes2/2011_Dist.shp")
india.dist@data <- merge(india.dist@data,nr1[,c(1,3)],by="DISTRICT")
india.dist@data$id <- rownames(india.dist@data)
ss.fort <- fortify(india.dist)
ss.fort1 <- merge(ss.fort, india.dist@data, by="id")

d <- ggplot() +
     geom_polygon(data = ss.fort1,
                  aes(x = long, y = lat, group = group, fill=reg.cases)) +
     coord_equal()

我有两个问题： 1.我想单独绘制一个状态。我对形状文件进行了子设置，并尝试使用类似的代码进行绘图。当我使用 fortify 命令时出现问题。该命令创建一个 id 列，其中包含从原始数据中提取的 ID，即 india.dist 而不是子文件。因此，当我将 state.fort 与 state@data 合并时，我没有得到正确的合并。还是很迷茫，不知道怎么重置ID。

state <- kr
state@data$id <- rownames(state@data)
state.fort <- fortify(state)
state.fort1 <- merge(state.fort, state@data, by="id")
unique(state.fort[,c(4:7)])
     hole piece  id group
1    FALSE     1   7   7.1
363  FALSE     1 173 173.1
719  FALSE     1 232 232.1
1384 FALSE     1 277 277.1
1960  TRUE     2 277 277.2
2013 FALSE     1 288 288.1
2561 FALSE     1 314 314.1
3018 FALSE     1 320 320.1
3349 FALSE     1 321 321.1
3753 FALSE     1 358 358.1
4144 FALSE     1 422 422.1
4735 FALSE     1 436 436.1
5204 FALSE     1 567 567.1
5663 FALSE     1 571 571.1
6292 FALSE     1 610 610.1

state@data
             DISTRICT  ST_NM ST_CEN_CD DT_CEN_CD censuscode reg.cases id
1           Alappuzha Kerala        32        11        598       259  1
2           Ernakulam Kerala        32         8        595       769  2
3              Idukki Kerala        32         9        596        42  3
4              Kannur Kerala        32         2        589        50  4
5           Kasaragod Kerala        32         1        588        38  5
6              Kollam Kerala        32        13        600       381  6
7            Kottayam Kerala        32        10        597        63  7
8           Kozhikode Kerala        32         4        591       237  8
9          Malappuram Kerala        32         5        592        95  9
10           Palakkad Kerala        32         6        593        31 10
11     Pathanamthitta Kerala        32        12        599        30 11
12 Thiruvananthapuram Kerala        32        14        601        97 12
13           Thrissur Kerala        32         7        594        99 13
14            Wayanad Kerala        32         3        590        39 14

第二个问题是：我怀疑 ggplot 没有正确地将数据（案例）与地区匹配。它通过给错误的区域提供错误的阴影来使数据不匹配。我不知道如何检查这种不匹配是否没有发生，如果发生了那么如何解决。我认为这个问题还涉及处理形状文件中的 ID。

我很感激任何关于这方面的指导。提前致谢。

Answer 1

这就是你的想法。在交换了所有评论之后，我认为这可能就是您所追求的。如果需要创建所有地图，只需删除lapply()中的[1:2]即可。您还想检查 reg.cases 的最小值和最大值。在当前示例中，我有 24 和 240。您的真实数据会有不同的值。调整 scale_fill_gradientn() 中的限制。最后，确保在最后一行中删除 [1:2]。抱歉，时间太短了，但这是我现在可以为您做的。

library(rgdal)
library(dplyr)
library(ggplot2)
library(ggthemes)

### Import data. I am using Mac here.
india <- readOGR(dsn = ".", layer = "2011_Dist", stringsAsFactors = FALSE)

### Just get data for the district names in nr1.
temp <- subset(india, DISTRICT %in% nr1$DISTRICT)

### Add reg.cases by merging the two
x <- merge(temp, nr1, by = "DISTRICT")

### Get district names for the lapply part.
ana <- x$DISTRICT

### Subset data, get reg.cases value, fortify the SPdataframe,
### add reg.cases to the fortified data frame. Then, draw graphics.

foo <- lapply(ana[1:2], function(y){

             temp <- subset(x, x@data$DISTRICT == y)
             whatever <- temp@data$reg.cases
             temp2 <- fortify(temp) %>%
                      mutate(hue = whatever)

             g <- ggplot() +
                  geom_map(data = temp2, map = temp2,
                           aes(x = long, y = lat, map_id = id, group = group,
                           fill = hue)) +
             scale_fill_gradientn(limits = c(24, 240),
                                  colors = c("blue", "red"),
                                  name = "reg.cases") +
             coord_map() + 
             theme_map()
             g
           })

 # If you print all maps, delete [1:2] in the following line.
 invisible(mapply(ggsave, file=paste0(ana[1:2], ".png"), plot = foo))

数据

nr1 <- structure(list(DISTRICT = structure(1:14, .Label = c("Alappuzha", 
"Ernakulam", "Idukki", "Kannur", "Kasaragod", "Kollam", "Kottayam", 
"Kozhikode", "Malappuram", "Palakkad", "Pathanamthitta", "Thiruvananthapuram", 
"Thrissur", "Wayanad"), class = "factor"), ST_NM = structure(c(1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = "Kerala", class = "factor"), 
reg.cases = c(54L, 84L, 45L, 137L, 140L, 171L, 152L, 20L, 
57L, 184L, 25L, 103L, 94L, 215L)), .Names = c("DISTRICT", 
"ST_NM", "reg.cases"), row.names = c(NA, -14L), class = "data.frame")

子设置形状文件以绘制区域并解决 ggplot 和数据中的不匹配问题

Sub setting shape file to plot a region and addressing mismatch in ggplot & data

r

shape

ggplot2