在空间点数据框架中绘制空间多边形数据框架。

Question

我有一个SpatialPolygonsDataFrame，我使用以下命令进行绘制：

```r plot(my_SPDF) ```

spplot(milanoNILNew, "percPolVita",at = c(0,0.0696,0.08979,0.0974,0.1116,0.181),col.regions =pal,main="Quota Clienti Unipol con Polizze Vita ")

我使用以下命令创建了一个spatialPointsDataFrame

agenziePoints<-SpatialPointsDataFrame(coords=datiAgenzie[,c("Long","Lat")],data=datiAgenzie,proj4string = llCRS, match.ID = TRUE).

我能够绘制多边形，但我无法在同一图中表示多边形上的agenziePoints。提前感谢您的支持。

- Giorgio Spedicato

Answer 1

只需使用带有add=TRUE参数的基本绘图函数即可。

require(sp)

# Create polygons
sr=SpatialPolygons(list(
  Polygons(list(Polygon(cbind(c(180114,180553,181127,181477,181294,181007,180409, 
  180162,180114),c(332349, 332057, 332342, 333250, 333558, 333676, 332618, 332413, 332349)))),"1"),
  Polygons(list(Polygon(cbind(c(180042,180545,180553,180314,179955,179142,179437,179524,179979,180042), 
  c(332373,332026,331426,330889,330683,331133,331623,332152,332357,332373)))),"2")))
srdf=SpatialPolygonsDataFrame(sr, data.frame(cbind(1:2,1:2), row.names=c("1","2")))

# Add points (sp meuse dataset)
data(meuse)
coordinates(meuse) = ~x+y

# Create a color vector for the meuse points
color <- rep("xx", nrow(meuse@data))
  color[(meuse@data$copper > 0)&(meuse@data$copper <= 31)] <- "black"
    color[(meuse@data$copper  > 31)] <- "red"

# Plot polygons with points overlaid    
plot(srdf, col=c("grey","blue"))
  plot(meuse, col=color, pch=19, add=TRUE) 

如果你真的想使用spplot函数，你可以实现类似这样的代码：

# spplot approach
pts=list("sp.points", meuse, pch=19, col=color)
  spplot(srdf, "X1", col.regions=c("grey","blue"), colorkey=FALSE,
         sp.layout=list(pts)) 

- Jeffrey Evans