如何在 leaflet plot 中为 r 设置插值栅格的投影？

Question

我正在尝试将光栅图像添加到 leaflet。 虽然对我的插值并不完全满意，但我确实有一个通过正常的plot function 绘制。 我在下面显示的代码应该能够独立运行，因为我为输入数据提供了示例数据。

ozone_df<-data.frame("Longitude"=runif(200, -112.245075*10000,-111.455581*10000)/10000)
ozone_df$Latitude<-runif(200, 40.063614*10000,40.827281*10000)/10000
ozone_df$Ozone<-runif(200, 0,115)

#create grid tick marks
small_grid_x = seq(-111.455581,-112.245075,length.out=500)
small_grid_y = seq(40.063614,40.827281,length.out=500)
#create grid nodes
krig_grid_small<-expand.grid(small_grid_x,small_grid_y)
coordinates(krig_grid_small) <- ~ Var1 + Var2
#create kriging fit and apply interpolation to grid
krig_fit_small<-fields::Krig(ozone_df[1:2],ozone_df$Ozone)
ozone_krig_small<-raster::interpolate(grid_raster_small, krig_fit_small)
crs(ozone_krig_small) <-CRS("+proj=longlat +ellps=WGS84 +datum=WGS84")
#plot output raster
plot(ozone_krig_small)

leaflet() %>% 
  addRasterImage(ozone_krig_small, project=T)%>% 
  addTiles() %>% 
  setView(lng = -111.941004,  40.610497, zoom = 10) %>% 
  addMiniMap()

Even though this plots with plot, when I try to add it to the leaflet I get Error in wkt(projfrom): could not find function "wkt" , which seems to be because I haven't set up the coordinates correctly for the raster图片。

Answer 1

如果您更新软件包（或至少是光栅、sp 和 rgdal），则该错误应消除 go --- 使用 R >= 4 也很好。

这是一个包含一些对我有用的修复的版本

library(raster)
library(leaflet)
library(fields)
ozone_df<-data.frame("Longitude"=runif(200, -112.245075*10000,-111.455581*10000)/10000)
ozone_df$Latitude<-runif(200, 40.063614*10000,40.827281*10000)/10000
ozone_df$Ozone<-runif(200, 0,115)

#create grid tick marks
small_grid_x = seq(-111.455581,-112.245075,length.out=500)
small_grid_y = seq(40.063614,40.827281,length.out=500)

#create grid nodes
krig_grid_small <- expand.grid(small_grid_x,small_grid_y)
coordinates(krig_grid_small) <- ~ Var1 + Var2

#create kriging fit and apply interpolation to grid
krig_fit_small<-fields::Krig(ozone_df[1:2],ozone_df$Ozone)

grid_raster_small = rasterFromXYZ(krig_grid_small)
ozone_krig_small<-raster::interpolate(grid_raster_small, krig_fit_small)
crs(ozone_krig_small) <-CRS("+proj=longlat +ellps=WGS84 +datum=WGS84")
#plot output raster
plot(ozone_krig_small)

leaflet() %>% 
  setView(lng = -111.941004,  40.610497, zoom = 10) %>% 
  addTiles() %>% 
  addRasterImage(ozone_krig_small, project=T)%>% 
  addMiniMap()