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I have counted pixels with NDVI more than 0.2 for each polygon in a shapefile. Now I want to create choropleth map showing counts of pixels in each polygon. I want to how to create choropleth map after using reduceregions command.

green_areas mean pixels with NDVI more than 0.2 test is shapefile

var  sumgreen  =  green_areas.reduceRegions({
  collection: test # my shapefile 
  reducer: ee.Reducer.count(),
  scale: 10,
});
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  • 1
    Please Edit your Question to contain a question. The question body should contain a description of the task, what you have tried, and the error or problem encountered. The title should be a brief summary of the Question topic, written after the question is completed.
    – Vince
    Jun 25, 2021 at 12:37
  • 1
    I rewrote your title, but a Question here is not just a statement of what you want to accomplish, but what you have tried and what error or problem you have encountered.
    – Vince
    Jun 25, 2021 at 12:47
  • Thanks for edits , which commands of GEE I should use to display count of green (more than 0.2 NDVI) pixels in each polygon . Polygon 1 has 35 , polygon 2 has 56 ...and son on . I did used paint empty image . Jun 25, 2021 at 12:52
  • 1
    Please Edit the Question to contain any details you want folks to see. Comments are really only to request clarifications.
    – Vince
    Jun 25, 2021 at 12:56

1 Answer 1

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I've had success converting my featureCollection to raster then plotting the featureCollection (with transparency) on top of the raster.

// bottom-left, top-right
var aoi = ee.Geometry.Rectangle(43.1, 13, 47, 30);

var ecoregions = ee.FeatureCollection('RESOLVE/ECOREGIONS/2017')
  .filterBounds(aoi);

var ecoregions_img = ecoregions
  .filter(ee.Filter.notNull(['SHAPE_AREA']))
  .reduceToImage({
    properties: ['SHAPE_AREA'],
    reducer: ee.Reducer.first()
});

var area_values = ecoregions
  .filter(ee.Filter.greaterThan("SHAPE_AREA", 0))
  .aggregate_array("SHAPE_AREA");
print(area_values) // 0 - 72


Map.centerObject(ecoregions, 4)
Map.addLayer(ecoregions_img, {
  min: 0,
  max: 73,
  palette: ['FCFDBF', 'FDAE78', 'EE605E', 'B63679', '711F81', '2C105C']
});
Map.addLayer({eeObject: ecoregions.draw({color: 'black', strokeWidth: 1}), visParams: {}, opacity: 0.3});

enter image description here

See https://developers.google.com/earth-engine/guides/reducers_reduce_to_image

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