Apply a reducer to each element of a collection, using the given selectors to determine the inputs.
Returns a dictionary of results, keyed with the output names.
ImageCollection.reduceColumns(reducer, selectors, weightSelectors)
|FeatureCollection||The collection to aggregate over.|
|Reducer||The reducer to apply.|
|List||A selector for each input of the reducer.|
|List, default: null||A selector for each weighted input of the reducer.|