请高手帮忙看看这个Script有什么问题

主要是想实现：昨天的最低点是前天、昨天、今天这三天的最低点，并今天的最低点在10天最低点之内ATR（10）距离，则在今天收盘价附近买入，止损为买入价格-ATR（10）。当价格达到10天最高点-0.5*ATR（10）之后卖出。
但是脚本写出来以后，交易次数很少。我检查了一下，不知道哪里有问题，请高手帮忙看看。
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var ChannelUp, ChannelDn: integer;
var N, L1, L2, LE, LS, Account, Tick: float;
var Bar, p, LeadBars, ATRParam : integer;

{ Parameters input }
ChannelUp := 10 ;
ChannelDn := 10 ;
ATRParam := 10 ;
Account := 1000000 ; //This is the notional account

{ Cosmetics and general info }
HideVolume ;
PlotStops;
EnableNotes(false);
tick := GetTick ;

{ Indicators plotting }
PlotSeries( HighestSeries( #High, ChannelUp ), 0, #blue, #Thin );
PlotSeries( LowestSeries( #Low, ChannelDn ), 0, #green, #Dotted );

{ MAIN CYCLE }
LeadBars := Trunc(ChannelUp); // Failsafe > Channel and Failsafe > Exit
for Bar := LeadBars to BarCount - 1 do
begin
N := ATR( Bar, ATRParam ); // N calculation
LE := Highest( Bar, #High, ChannelUp) - 0.5 * N ;

{ Entering the first position }
if (PositionCount = 0)and(PriceLow( Bar - 2 ) > PriceLow( Bar - 1 ))
and(PriceLow( Bar - 1 ) < PriceLow( Bar ))
and (PriceClose( Bar ) < Lowest( Bar , #Low, ChannelDn) + N) then
begin
SetShareSize(Int( (Account * 0.01) / (N * GetPointValue*100))*100); // Unit Using China
L1 := PriceClose( Bar ) ;
L2 := L1 + 0.5 * N ;
BuyAtStop( Bar , L1, 'L1 ' + FormatFloat( '#0.00', L1));
LS := L1 - N;
end; // of 'if PositionCount = 0 then'

{ Check for position exit conditions }
for p := 0 to PositionCount -1 do begin
if PositionActive(p) then begin
if not SellAtStop( Bar + 1, LS, p, 'LongStop' + FormatFloat('#0.00', LS)) then
SellAtStop( Bar + 1, LE, p, 'LongExit' + FormatFloat('#0.00', LE));
end;
end; // of position exits
end; // OF THE MAIN CYCLE