Clipping data to shapefile using Google Earth Engine?

Question

I want to clip this fire data so it only displays results in my shapefile titled 'tapajos'. How do I do this?

var dataset = ee.ImageCollection('FIRMS').filter(
    ee.Filter.date('2000-01-01', '2018-08-10'));
var fires = dataset.select('T21');
var firesVis = {
  min: 325.0,
  max: 400.0,
  palette: ['red', 'orange', 'yellow'],
};
Map.setCenter(-119.086, 47.295, 6);
Map.addLayer(fires, firesVis, 'Fires');

Answer 1

You can clip every image in the collection by using:

// This function clips images to the ROI feature collection
var clipToCol = function(image){
  return image.clip(tapajos);
};
var dataset = ee.ImageCollection('FIRMS').filter(
    ee.Filter.date('2000-01-01', '2018-08-10')).map(clipToCol);
var fires = dataset.select('T21');
var firesVis = {
  min: 325.0,
  max: 400.0,
  palette: ['red', 'orange', 'yellow'],
};
Map.setCenter(-119.086, 47.295, 6);
Map.addLayer(fires, firesVis, 'Fires');

Answer 2

When you say Map.addLayer(fires,...), you're implicitly calling mosaic() on that collection, which returns a single image. If that's how you're doing it, clipping a single image (a composite) to a FeatureCollection, then you should use image.clipToCollection(). If you need to clip every image in the collection first, then map a function over the ImageCollection in which you call clipToCollection().