求教MT4平台上KDJ指标的源代码应该怎么写？

                      在MT4平台上编写KDJ指标的源代码需要一定的编程知识。首先，你需要了解KDJ指标的基本计算方法：通常包括K值、D值和J值的计算。你可以参考以下简单的示例开始：

```plaintext
//+------------------------------------------------------------------+
//|                                                   KDJ Indicator |
//|                        Copyright 2023, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property indicator_chart_window
#property indicator_buffers 3
#property indicator_color1 Blue
#property indicator_color2 Red
#property indicator_color3 Green

double KBuffer[];
double DBuffer[];
double JBuffer[];

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int OnInit()
  {
   SetIndexBuffer(0,KBuffer);
   SetIndexBuffer(1,DBuffer);
   SetIndexBuffer(2,JBuffer);
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                               |
//+------------------------------------------------------------------+
int OnCalculate(const int rates_total,
                const int prev_calculated,
                const datetime &time[],
                const double &open[],
                const double &high[],
                const double &low[],
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
  {
   // 在这里实现KDJ的具体计算逻辑
   return(rates_total);
  }
//+------------------------------------------------------------------+
```

以上仅为基本框架，具体计算部分需根据实际需求填充。建议初学者查阅相关资料或向专业人士咨询。请注意，自行修改指标可能影响交易决策准确性。