对 RasterLayer 使用 RasterPackage 的“提取”会导致 R 中的错​​误

Question

I want to merge precipitation data with a .csv df. I figured out, that it should work with the command "extract" from the raster package. That's my precipitation data:

str(precipitation_raster_layer)
Formal class 'RasterLayer' [package "raster"] with 12 slots
  ..@ file    :Formal class '.RasterFile' [package "raster"] with 13 slots

Thats my climate-related Aid data:

str(AID)
'data.frame':   1050 obs. of  21 variables:
 $ project_location_id     : Factor w/ 1050 levels "P000501_2427123",..: 189 190 191 192 193 194 188 195 196 187 ...
 $ precision_code          : int  3 3 3 3 3 3 3 3 3 2 ...
 $ latitude                : num  6.45 6.74 6.47 5.66 6.6 ...
 $ longitude               : num  -1.583 -3.044 -2.333 -0.39 0.467 ...

Using this command:

test <- extract(precipitation_raster_layer, AID[,3:4])

Error in UseMethod("extract_") : no applicable method for 'extract_' applied to an object of class "c('RasterLayer', 'Raster', 'BasicRaster')"

If I transform the .csv to a SpatialPointsDataFrame and try to run "extract", I get this error:

test <- extract(precipitation_raster_layer, AID_spatial_df)

Error in UseMethod("extract_") : no applicable method for 'extract_' applied to an object of class "c('RasterLayer', 'Raster', 'BasicRaster')"

I really do not understand why it says that my object is not a RasterLayer.

Any help appreciated.

Answer 1

My guess is that you have, after loading raster , loaded another package that also has an extract method that hides the method from raster .

Load only the packages you need, and try calling the extract method from raster explicitly:

raster::extract(precipitation_raster_layer, AID[, 4:3])

Note that it should be AID[, 4:3] , not AID[, 3:4] , as the correct order is longitude, latitude. But that is not the cause of the error you are getting.

Answer 2

您可能已经加载了 tidyverse，卸载它并重试