我正在尝试将地理数据库文件 (.gdb) 中包含的 shapefile 读取到 R 中。.gdb 包含两个要素数据集,每个数据集具有多个要素类。
问题是只有两个特征数据集之一正在被读取。
具体来说,我对所有州使用 NHD 数据集 ftp://nhdftp.usgs.gov/DataSets/Staged/States/FileGDB/HighResolution/
在每个状态 .gdb 中有两个特征数据集,“WBD”和“Hydrography”。仅读取“WBD”。使用 ogrListLayers 仅返回来自“WBD”的图层。如何指定“Hydrography”数据集并访问其中的要素类?
任何建议将不胜感激。
R 版本 3.2.0。 OSX v.10.10.3
编辑 06/16/15:
当我运行 orgListLayers 时,它返回:
ogrListLayers('NHDH_VI.gdb')
[1] "ExternalCrosswalk" "NHDFCode" "NHDFeatureToMetadata"
[4] "NHDFlow" "NHDFlowlineVAA" "NHDMetadata"
[7] "NHDProcessingParameters" "NHDReachCodeMaintenance" "NHDReachCrossReference"
[10] "NHDSourceCitation" "NHDStatus" "NHDVerticalRelationship"
[13] "WBDHU14" "WBDHU8" "WBDHU2"
[16] "WBDHU4" "WBDHU6" "WBDHU10"
[19] "WBDHU12" "WBDHU16" "HYDRO_NET_Junctions"
21 层不同,然后由 Mike T 和 hrbrmstr 表示。具体来说,我正在寻找:图层名称:NHDWaterbody。
当我跑
ogrinfo -ro NHDH_VI.gdb
从终端。ERROR 1: Error: Failed to open Geodatabase (This release of the GeoDatabase is either invalid or out of date.)
FAILURE: Unable to open datasource `NHDH_VI.gdb' with the following drivers.
-> FileGDB
-> OpenFileGDB
...
最佳答案
您可能正在阅读带有 ESRI File Geodatabase (OpenFileGDB) 的文件司机。 OGR 不保留或使用要素数据集,因此所有要素类都混合在同一个平面命名空间中。在 ArcCatalog 中查看(例如)NHDH_VI.gdb:
然后使用 ogrinfo -ro NHDH_VI.gdb
从命令行提示符读取相同的文件
INFO: Open of `NHDH_VI.gdb'
using driver `OpenFileGDB' successful.
1: NHDPoint (Point)
2: NHDFlowline (Multi Line String)
3: NHDLine (Multi Line String)
4: NHDArea (Multi Polygon)
5: NHDWaterbody (Multi Polygon)
6: NHDAreaEventFC (Multi Polygon)
7: NHDLineEventFC (Multi Line String)
8: NHDPointEventFC (Point)
9: WBDLine (Multi Line String)
10: NonContributingDrainageArea (Multi Polygon)
11: NWISBoundary (Multi Line String)
12: NWISDrainageArea (Multi Polygon)
13: WBDHU14 (Multi Polygon)
14: WBDHU8 (Multi Polygon)
15: WBDHU2 (Multi Polygon)
16: WBDHU4 (Multi Polygon)
17: WBDHU6 (Multi Polygon)
18: WBDHU10 (Multi Polygon)
19: WBDHU12 (Multi Polygon)
20: WBDHU16 (Multi Polygon)
21: HYDRO_NET_Junctions (Point)
同样可以从 R 中获得:
> library(rgdal)
> ogrListLayers("NHDH_VI.gdb")
[1] "NHDPoint" "NHDFlowline"
[3] "NHDLine" "NHDArea"
[5] "NHDWaterbody" "NHDAreaEventFC"
[7] "NHDLineEventFC" "NHDPointEventFC"
[9] "WBDLine" "NonContributingDrainageArea"
[11] "NWISBoundary" "NWISDrainageArea"
[13] "WBDHU14" "WBDHU8"
[15] "WBDHU2" "WBDHU4"
[17] "WBDHU6" "WBDHU10"
[19] "WBDHU12" "WBDHU16"
[21] "HYDRO_NET_Junctions"
attr(,"driver")
[1] "OpenFileGDB"
attr(,"nlayers")
[1] 21
因此,您需要手动将 ArcCatalog 层次结构中的数据集过滤为您可以从 OGR 中找到的数据。并非所有类都可用于 OGR(例如非空间表、关系类)。
关于在 R 中具有多个特征数据集的 readOGR .gdb,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30851510/