Google Earth Engine（GEE）——用10米分辨率土地分类数据进行土地面积计算出现错误

错误：

FeatureCollection (Error)

Error in map(ID=0): Feature, argument 'geometry': Invalid type. Expected type: Geometry. Actual type: Feature.

原始代码：

  

   

    

     

    
    

     

      var boten = ee.FeatureCollection("projects/ee-suraj7-28/assets/Boten");
     
    
   

    

     

    
    

     

      var boten_shp = boten.geometry()
     
    
   

    

     

    
    

     

      var Lunagprabang = ee.FeatureCollection("projects/ee-suraj7-28/assets/Luangprabang");
     
    
   

    

     

    
    

     

      var Lunagprabang_shp = Lunagprabang.geometry()
     
    
   

    

     

    
    

     

      var Vientiana = ee.FeatureCollection("projects/ee-suraj7-28/assets/Vientiana");
     
    
   

    

     

    
    

     

      var Vientiana_shp = Vientiana.geometry()
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      // Buffer//
     
    
   

    

     

    
    

     

      var boten_buffer=boten_shp.buffer(20000)
     
    
   

    

     

    
    

     

      var Lunagprabang_buffer=Lunagprabang_shp.buffer(20000)
     
    
   

    

     

    
    

     

      var Vientiana_buffer=Vientiana_shp.buffer(20000)
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      var features = ee.FeatureCollection([
     
    
   

    

     

    
    

     

        ee.Feature(boten_buffer, {label: 'Boten'}),
     
    
   

    

     

    
    

     

        ee.Feature(Lunagprabang_buffer, {label: 'Lunagprabang'}),
     
    
   

    

     

    
    

     

        ee.Feature(Vientiana_buffer, {label: 'vientiana'}),
     
    
   

    

     

    
    

     

      ])
     
    
   

    

     

    
    

     

      print(features)
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      var years = ee.List.sequence(2021,2022)
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      var calculateClassAreaByYear = features.map(function(feature){
     
    
   

    

     

    
    

     
  var dw2=years.map(function(year){
     
    
   

    

     

    
    

     
  var dw1= ee.ImageCollection('GOOGLE/DYNAMICWORLD/V1')
     
    
   

    

     

    
    

     

                    .filterDate(ee.Date.fromYMD(year, 1, 1), ee.Date.fromYMD(year, 12, 1)).filter(ee.Filter.bounds(feature)).select('label').reduce(ee.Reducer.mode()).eq(6);
     
    
   

    

     

    
    

     
              return dw1
     
    
   

    

     

    
    

     

                    })
     
    
   

    

     

    
    

     
              return ee.FeatureCollection(dw2)
     
    
   

    

     

    
    

     

          })
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      print(calculateClassAreaByYear.flatten())
     
    
  
 

  
 
 

我们这里可以看到提示期待的类型不对，需求的类型是几何图形，但是这里给的确实矢量，所以我们需要再后面加一个.geometry()

修改后的代码：

  

   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      var years = ee.List.sequence(2021,2022)
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      var calculateClassAreaByYear = features.map(function(feature){
     
    
   

    

     

    
    

     
  var dw2=years.map(function(year){
     
    
   

    

     

    
    

     
  var dw1= ee.ImageCollection('GOOGLE/DYNAMICWORLD/V1')
     
    
   

    

     

    
    

     

                    .filterDate(ee.Date.fromYMD(year, 1, 1), ee.Date.fromYMD(year, 12, 31)).filter(ee.Filter.bounds(feature.geometry())).select('label').reduce(ee.Reducer.mode()).eq(6);
     
    
   

    

     

    
    

     
  var areaImage = dw1.multiply(ee.Image.pixelArea())    
     
    
   

    

     

    
    

     
  var area = areaImage.reduceRegion({
     
    
   

    

     

    
    

     
  reducer: ee.Reducer.sum(),
     
    
   

    

     

    
    

     
  geometry: feature.geometry(),
     
    
   

    

     

    
    

     
  scale: 10,
     
    
   

    

     

    
    

     
  maxPixels: 1e10
     
    
   

    

     

    
    

     

        })
     
    
  
 

  
 
 

 这里有一个矢量面积的计算函数：

ee.Image.pixelArea()
Generate an image in which the value of each pixel is the area of that pixel in square meters. The returned image has a single band called "area."

ee.Image.pixelArea()
生成一个图像，其中每个像素的值是该像素的面积，单位是平方米。返回的图像有一个称为 "面积 "的单带。

文章来源: blog.csdn.net，作者：此星光明，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/qq_31988139/article/details/126406202