Indicators

class SymbolData(object):
    def __init__(self, symbol):
        self._symbol = symbol
        self.tolerance = 1.01
        self.fast = ExponentialMovingAverage(100)
        self.slow = ExponentialMovingAverage(300)
        self.is_uptrend = False
        self.scale = 0

    def update(self, time, value):
        if self.fast.update(time, value) and self.slow.update(time, value):
            fast = self.fast.current.value
            slow = self.slow.current.value
            self.is_uptrend = fast > slow * self.tolerance

        if self.is_uptrend:
            self.scale = (fast - slow) / ((fast + slow) / 2.0)

private class SelectionData
{
    public readonly ExponentialMovingAverage Fast;
    public readonly ExponentialMovingAverage Slow;

    public SelectionData()
    {
        Fast = new ExponentialMovingAverage(100);
        Slow = new ExponentialMovingAverage(300);
    }

    public decimal ScaledDelta
    {
        get { return (Fast - Slow)/((Fast + Slow)/2m); }
    }

    public bool Update(DateTime time, decimal value)
    {
        return Fast.Update(time, value) && Slow.Update(time, value);
    }
}

class EmaCrossUniverseSelectionAlgorithm(QCAlgorithm):

    def initialize(self) -> None:
        '''Initialise the data and resolution required, as well as the cash and start-end dates for your algorithm. All algorithms must initialized.'''

        self.set_start_date(2010,1,1)  #Set Start Date
        self.set_end_date(2015,1,1)    #Set End Date
        self.set_cash(100000)           #Set Strategy Cash
        self.universe_settings.asynchronous = True
        self.universe_settings.resolution = Resolution.DAILY
        self.universe_settings.leverage = 2

        self.count = 10
        self.averages = { }

        # this add universe method accepts two parameters:
        # - fundamental selection function: accepts an IEnumerable<Fundamental> and returns an IEnumerable<Symbol>
        self.add_universe(self.fundamental_selection_function)


    # sort the data by daily dollar volume and take the top 'NumberOfSymbols'
    def fundamental_selection_function(self, fundamental: list[Fundamental]) -> list[Symbol]:

        # We are going to use a dictionary to refer the object that will keep the moving averages
        for f in fundamental:
            if f.symbol not in self.averages:
                self.averages[f.symbol] = SymbolData(f.symbol)

            # Updates the SymbolData object with current EOD price
            avg = self.averages[f.symbol]
            avg.update(f.end_time, f.adjusted_price)

        # Filter the values of the dict: we only want up-trending securities
        values = list(filter(lambda x: x.is_uptrend, self.averages.values()))

        # Sorts the values of the dict: we want those with greater difference between the moving averages
        values.sort(key=lambda x: x.scale, reverse=True)

        for x in values[:self.count]:
            self.log('symbol: ' + str(x.symbol.value) + '  scale: ' + str(x.scale))

        # we need to return only the symbol objects
        return [ x.symbol for x in values[:self.count] ]

namespace QuantConnect.Algorithm.CSharp
{
    public class EmaCrossUniverseSelectionAlgorithm : QCAlgorithm
    {
        // tolerance to prevent bouncing
        const decimal Tolerance = 0.01m;
        private const int Count = 10;
        // use Buffer+Count to leave a little in cash
        private const decimal TargetPercent = 0.1m;
        private SecurityChanges _changes = SecurityChanges.None;
        // holds our fundamental indicators by symbol
        private readonly ConcurrentDictionary<Symbol, SelectionData> _averages = new ConcurrentDictionary<Symbol, SelectionData>();
    
        public override void Initialize()
        {
            UniverseSettings.Asynchronous = true;
            UniverseSettings.Leverage = 2.0m;
            UniverseSettings.Resolution = Resolution.Daily;
            SetStartDate(2010, 01, 01);
            SetEndDate(2015, 01, 01);
            SetCash(100*1000);

            AddUniverse(fundamental =>
            {
                return (from f in fundamental
                        // grab th SelectionData instance for this symbol
                        let avg = _averages.GetOrAdd(f.Symbol, sym => new SelectionData())
                        // Update returns true when the indicators are ready, so don't accept until they are
                        where avg.Update(f.EndTime, f.AdjustedPrice)
                        // only pick symbols who have their 50 day ema over their 100 day ema
                        where avg.Fast > avg.Slow*(1 + Tolerance)
                        // prefer symbols with a larger delta by percentage between the two averages
                        orderby avg.ScaledDelta descending
                        // we only need to return the symbol and return 'Count' symbols
                        select f.Symbol).Take(Count);
            });
        }
    }
}