st_write 拒绝在 R 中覆盖地理包中的图层

Question

使用 R 中的 sf 包，我正在读取存储在地理包中的一系列图层，过滤它们，然后将它们重新保存为新的地理包。
当我设置我的脚本时，我测试了其中一个层并且它工作正常，但是当运行然后层列表上的相同代码时，它失败了，因为测试层已经存在。 st_write 的文档同时包含追加和覆盖参数，但设置为替换而不是追加（append = FALSE 或 overwrite = TRUE）会导致失败并显示错误

Error in st_write.sf(., dsn = gpkg_out, layer = layername, overwrite = TRUE) : unrecognized argument(s) overwrite

Error in st_write.sf(., dsn = gpkg_out, layer = layername, append = FALSE) : unrecognized argument(s) append

我更新了 sf 包的副本，但它仍然失败并出现相同的错误。我通过删除文件系统中的文件找到了解决方法，但如果我只是想替换一层，这就会有问题。

有谁知道这是否是一个已知问题，或者是否有办法替换而不是附加图层？

我的代码：

library(sf)
library(tidyverse)

gpkg <- "D:/GIS/Sugar/SugarEC_hydropts.gpkg"  # name of existing geopackage

layers = st_layers(gpkg)$name
layers
# [1] "ec1520"  "ec17200" "ec224"   "ec2500" 
#  "ec271"   "ec4680"  "ec488"   "ec5540"  "ec8140"  "ec9860" 

gpkg_out <- "D:/GIS/Sugar/SugarEC_hydropts_wet.gpkg"

# the following works, but appends to layer if it exists
read_write <-  function (layername) {
      st_read(gpkg, layer = layername ) %>%
      filter(Water_Elev_ft >0) %>%
      st_write(dsn = gpkg_out, layer = layername)  # Appends
#   
#   This following versions fails though:
#     st_write(dsn = gpkg_out, layer = layername, overwrite = TRUE) 
#   or
#     st_write(dsn = gpkg_out, layer = layername, append = FALSE)

      invisible()
}

lapply(layers, read_write)

Answer 1

如果数据可能已经存在，您似乎需要使用 delete_dsn = TRUE。如果数据不存在，将抛出警告，但仍会写入文件。

nc <-  read_sf(system.file("shape/nc.shp", package="sf"))

Reading layer `nc' from data source `/home/mrhellmann/R/x86_64-pc-linux-gnu-library/3.6/sf/shape/nc.shp' using driver `ESRI Shapefile'
Simple feature collection with 100 features and 14 fields
geometry type:  MULTIPOLYGON
dimension:      XY
bbox:           xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965
epsg (SRID):    4267
proj4string:    +proj=longlat +datum=NAD27 +no_defs


st_write(nc, 'nc_test.shp', 'nc')

Writing layer `nc' to data source `nc_test.shp' using driver `ESRI Shapefile'
Writing 100 features with 14 fields and geometry type Multi Polygon.

## Error here, as it already exists.
st_write(nc, 'nc_test.shp', 'nc')

Dataset nc_test.shp already exists: remove first, use update=TRUE to append,
delete_layer=TRUE to delete layer, or delete_dsn=TRUE to remove the entire data source before writing.
Error in CPL_write_ogr(obj, dsn, layer, driver, as.character(dataset_options),  : 
  Dataset already exists.


# No error when delete_dsn = T
st_write(nc, 'nc_test.shp', 'nc', delete_dsn = T)

Deleting source `nc_test.shp' using driver `ESRI Shapefile'
Writing layer `nc' to data source `nc_test.shp' using driver `ESRI Shapefile'
Writing 100 features with 14 fields and geometry type Multi Polygon.


nc_saved <- read_sf('nc_test.shp')

identical(nc, nc_saved)
#[1] TRUE

Answer 2

在 GeoPackage 中使用 delete_layer = TRUE 到 overwrite/update 层。

st_write 拒绝在 R 中覆盖地理包中的图层

st_write refuses to overwrite layers in geopackage in R

r

spatial

sf

geopackage