求助！EA中如何调用该指标？

我有两年的外汇交易经验，今年以来运用一套超短线策略帐户资金开始出现增长。对于编程我有一些经验，对于EA我还是新手。我想将我的策略用EA来实现。

问题是：EA中用到指标slope direction line实现基本的趋势判断，但我不知到如何正确调用。

double iCustom( string symbol, int timeframe, string name, ..., int mode, int shift)

其中int mode是什么？具体对于slope direction line而言，mode应该是什么？下面语句中问号应该是什么？

if(iCustom(NULL,PERIOD_M30,"Slope Direction Line",10,2,4,？,0)==？&&.......) {.....//趋势向上}


slope direction line代码如下


//+------------------------------------------------------------------+
#property copyright " MT4 release WizardSerg <wizardserg@mail.ru>, ?? ??????? ForexMagazine #104"
#property link "wizardserg@mail.ru"

#property indicator_chart_window
#property indicator_buffers 2
#property indicator_color1 Blue
#property indicator_color2 Red
//---- input parameters
extern int period=10;
extern int method=2; // MODE_SMA
extern int price=4; // PRICE_CLOSE
//---- buffers
double Uptrend[];
double Dntrend[];
double ExtMapBuffer[];


//+------------------------------------------------------------------+
//| Custom indicator initialization function |
//+------------------------------------------------------------------+
int init()
{
IndicatorBuffers(3);
SetIndexBuffer(0, Uptrend);
//ArraySetAsSeries(Uptrend, true);
SetIndexBuffer(1, Dntrend);
//ArraySetAsSeries(Dntrend, true);
SetIndexBuffer(2, ExtMapBuffer);
ArraySetAsSeries(ExtMapBuffer, true);

SetIndexStyle(0,DRAW_LINE,STYLE_SOLID,2);
SetIndexStyle(1,DRAW_LINE,STYLE_SOLID,2);

IndicatorShortName("Slope Direction Line("+period+")");
return(0);
}

//+------------------------------------------------------------------+
//| Custor indicator deinitialization function |
//+------------------------------------------------------------------+
int deinit()
{
// ???? ????? ?????? ??????
return(0);
}

//+------------------------------------------------------------------+
//| ?????????? ??????? |
//+------------------------------------------------------------------+
double WMA(int x, int p)
{
return(iMA(NULL, 0, p, 0, method, price, x));
}

//+------------------------------------------------------------------+
//| Custom indicator iteration function |
//+------------------------------------------------------------------+
int start()
{
int counted_bars = IndicatorCounted();

if(counted_bars < 0)
return(-1);

int x = 0;
int p = MathSqrt(period);
int e = Bars - counted_bars + period + 1;

double vect[], trend[];

if(e > Bars)
e = Bars;

ArrayResize(vect, e);
ArraySetAsSeries(vect, true);
ArrayResize(trend, e);
ArraySetAsSeries(trend, true);

for(x = 0; x < e; x++)
{
vect[x] = 2*WMA(x, period/2) - WMA(x, period);
// Print("Bar date/time: ", TimeToStr(Time[x]), " close: ", Close[x], " vect[", x, "] = ", vect[x], " 2*WMA(p/2) = ", 2*WMA(x, period/2), " WMA(p) = ", WMA(x, period));
}

for(x = 0; x < e-period; x++)

ExtMapBuffer[x] = iMAOnArray(vect, 0, p, 0, method, x);

for(x = e-period; x >= 0; x--)
{
trend[x] = trend[x+1];
if (ExtMapBuffer[x]> ExtMapBuffer[x+1]) trend[x] =1;
if (ExtMapBuffer[x]< ExtMapBuffer[x+1]) trend[x] =-1;

if (trend[x]>0)
{ Uptrend[x] = ExtMapBuffer[x];
if (trend[x+1]<0) Uptrend[x+1]=ExtMapBuffer[x+1];
Dntrend[x] = EMPTY_VALUE;
}
else
if (trend[x]<0)
{
Dntrend[x] = ExtMapBuffer[x];
if (trend[x+1]>0) Dntrend[x+1]=ExtMapBuffer[x+1];
Uptrend[x] = EMPTY_VALUE;
}

//Print( " trend=",trend[x]);
}

return(0);
}
//+------------------------------------------------------------------+