Google Earth Engine：从年度观测中提取第二大值？

Question

在GoogleEarth Engine中，是否可以提取年度第二大和第二小的值并构建图像集？显然，没有用于此目的的内置减速器。这是我获取最小值的代码，请指导我如何获取 second 最大值和最小值。谢谢！

代码如下：

var startDate = ee.Date('2001-01-01'); // set start time for analysis
var endDate = ee.Date('2021-12-31'); // set end time for analysis

// calculate the number of year to process
var nyears = ee.Number(endDate.difference(startDate,'year'));

//init a time band
var createTimeBand= function(image) {
  return image.addBands(image.metadata('system:time_start')
  .divide(1e18))
 // .divide(1000*60*60*24*365))
}


var sst = ee.ImageCollection('MODIS/006/MOD11A1').select('LST_Day_1km')
            .filterDate(startDate, endDate)
            .map(createTimeBand)

var byyearMin = ee.ImageCollection(
  // map over each month
  ee.List.sequence(0,nyears).map(function (n) {
    // calculate the offset from startDate
    var ini = startDate.advance(n,'year');
    // advance just one month
    var end = ini.advance(1,'year');
    // filter and reduce
    return sst.filterDate(ini,end)
                .select(0).min()
              //  .sort('LST_Day_1km').reverse().first()
                .multiply(0.02)
                .subtract(273.15)
                .set('system:time_start', ini.millis());//convert time to number
}));

Answer 1

var startDate = ee.Date('2001-01-01'); // set start time for analysis
var endDate = ee.Date('2021-12-31'); // set end time for analysis

// calculate the number of year to process
var nyears = ee.Number(endDate.difference(startDate,'year'));

//init a time band
var createTimeBand= function(image) {
  return image.addBands(image.metadata('system:time_start')
  .divide(1e18))
 // .divide(1000*60*60*24*365))
}


var sst = ee.ImageCollection('MODIS/006/MOD11A1').select('LST_Day_1km')
            .filterDate(startDate, endDate)
            //.map(createTimeBand)
            
var byyearMin = ee.ImageCollection(
  // map over each month
  ee.List.sequence(0,nyears).map(function (n) {
    // calculate the offset from startDate
    var ini = startDate.advance(n,'year');
    // advance just one month
    var end = ini.advance(1,'year');
    
    var sortedDays = sst.filterDate(ini,end)
    .sort('LST_Day_1km')
    .toList(sst.size())
      
    var secondLargest = ee.List(sortedDays.get(1))
    var secondSmallest = ee.List(sortedDays.get(-1))
    
    var collection = ee.Image(secondLargest)
    .addBands(secondSmallest).rename(['secondLargest', 'secondSmallest'])
    .multiply(0.02)
      .subtract(273.15)
      return collection
      .set('system:time_start', ini.millis()) //convert time to number
      .set('Date', ee.Date(ini))
}));

print(byyearMin)

Google Earth Engine：从年度观测中提取第二大值？

Google Earth Engine: Extract second largest value from annual observations?

google-earth-engine