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我已经使用包 raster 和 rgdal 从 CSV 制作了 shapefile，但我想将这些 shapefile 剪辑到某个区域，我可以这样做。
但是，当我尝试 write.csv 时它不起作用。

另外，在 writeOGR 之后我丢失了 X 和 Y。

datansd = read.csv("..csv", header=T,sep=",")
### tell R what the coordinates are and define the coordinate system ###
coordinates(datansd) = c("X","Y")
proj4string(datansd) = CRS("+init=epsg:32614")
### write the shapefile, dsn is the target folder, layer is the name of the shapefile ###
writeOGR(datansd, dsn = "Shapes", layer = "July2013UD5", driver = "ESRI     Shapefile")
sdata <- readOGR(dsn="C:.", layer="July2013UD5")
# READ POINT SHAPEFILE TRAINING DATA
> head(sdata)    
  name       Value Value2      Value3 sampleID 
  1 29435 98.94331        1 1.056688    w764 
  2 29436 98.87749        1 1.122505    w764 
  3 29437 98.83189        1 1.168107    w764 
  4 29438 98.78847        1 1.211534    w764 
  5 29439 98.77276        1 1.227239    w764 
  6 29440 98.78549        1 1.214514    w764
> enclosure <- readOGR(dsn="C:.", layer="polygon")
  OGR data source with driver: ESRI Shapefile 
  Source: "C:..", layer: "polygon"
  with 12 features and 13 fields
  Feature type: wkbPolygon with 2 dimensions
> plot(enclosure)
> points(sdata)
> data <- spTransform(sdata, CRS(proj4string(enclosure))) # transform  CRS
> points(data)
> head(data)   
  name       Value Value2      Value3 sampleID 
  1 29435 98.94331        1 1.056688    w764 
  2 29436 98.87749        1 1.122505    w764 
  3 29437 98.83189        1 1.168107    w764 
  4 29438 98.78847        1 1.211534    w764 
  5 29439 98.77276        1 1.227239    w764 
  6 29440 98.78549        1 1.214514    w764
> data_subset <- data[enclosure, ]
> plot(enclosure)
> points(data_subset)
> head(data_subset)
    name     Value Value2   Value3 sampleID 
    378 31632 96.04780        1 3.952204    w764 
    379 31633 95.86989        1 4.130108    w764 
    380 31634 95.69978        1 4.300223    w764 
    381 31635 95.41422        1 4.585780    w764 
    382 31636 95.09640        1 4.903604    w764 
    383 31637 94.67770        1 5.322302    w764
> write.csv(data_subset,file ="C:...csv", row.names = FALSE)
> data_subset = read.csv("Shapes/July2013UD5clip.csv",  header=T,sep=",")
> coordinates(datansd) = c("X","Y")
    Error in `coordinates<-`(`*tmp*`, value = c("X", "Y")) : 
    setting coordinates cannot be done on Spatial objects, where they have already   been set
> writeOGR(data_subset, dsn = "Shapes", layer = "July2013UD5clip", driver =           "ESRI Shapefile")
    Error: inherits(obj, "Spatial") is not TRUE
> sdata <- readOGR(dsn="C:../Shapes", layer="July2013UD5clip")
    Error in ogrInfo(dsn = dsn, layer = layer, encoding = encoding, use_iconv        =      use_iconv,  : 
    Cannot open layer

当我将 X、Y 返回到 shapefile 属性表中时，我想将栅格值提取到点，然后将点的坐标和新属性写入 .csv。

如何在最终产品中获得 X、Y？

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1 回答 1

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在这条线之后

data_subset <- data[enclosure, ]

您有一个（子集）SpatialPointsDataFrame。您将其作为“shapefile”写入磁盘。如果你想把它写成一个表格（csv），带有坐标，你应该这样做

write.csv(data.frame(data_subset), 'file.csv')

要从栅格中提取值然后写入 csv 文件，您可以这样做

e <- extract(raster, data_subset)
d <- data.frame(data_subset, e) 
write.csv(d, 'file.csv')
于 2015-06-05T00:50:00.537 回答