Before we define precisely what Algocrowd indicators are, let us look at an example. Here is a simple Algocrowd indicator:

  1  // ac_cross_zero_bar.mq4
  2  // an Algocrowd predictor
  3  #property indicator_chart_window
  4  
  5  
  6  extern double margin = 1; // INT 1-1000
  7  extern int shift = 0; // INT 0-50
  8  extern int span = 1; // INT 1-49
  9
 10
 11  string symbol;
 12  int timeframe;
 13  
 14  
 15  double trade[];
 16
 17
 18  double ac;
 19  double old_ac;
 20
 21
 22  int init() {
 23
 24    SetIndexBuffer(0, trade);
 25    return(0);
 26  }
 27
 28
 29  int start() {
 30
 31    ac = iAC(symbol, timeframe, shift);
 32    old_ac = iAC(symbol, timeframe, span - shift);
 33
 34    if (old_ac < 0 - margin && ac > 0 + margin ) {
 35      trade[0] = 1;
 36    }
 37    else if (old_ac > 0 + margin && ac < 0 - margin) {
 38      trade[0] = -1;
 39    }
 40    else {
 41      trade[0] = 0;
 42    }
 43
 44    return(0);
 45  }

Here is an Algocrowd indicator that is configured for the different instruments:

  1  // ac_cross_zero_bar.mq4
  2  // an Algocrowd predictor
  3  #property indicator_chart_window
  4  
  5  
  6  extern string the_symbol;
  7  extern double margin = 1; // INT 1-1000
  8  extern int shift = 0; // INT 0-50
  9  extern int span = 1; // INT 1-49
 10
 11
 12  string symbol;
 13  int timeframe;
 14  
 15  
 16  double trade[];
 17
 18
 19  double ac;
 20  double old_ac;
 21
 22
 23  int init() {
 24
 25    if (the_symbol == "AUDCAD") {
 26      margin = margin / 2200000;
 27    }
 28
 29    else if (the_symbol == "AUDCHF") {
 30      margin = margin / 2200000;
 31    }
 32
 33    else if (the_symbol == "AUDJPY") {
 34      margin = margin / 22000;
 35    }
 36
 37    else if (the_symbol == "AUDUSD") {
 38      margin = margin / 2200000;
 39    }
 40
 41    else if (the_symbol == "CADCHF") {
 42      margin = margin / 2200000;
 43    }
 44
 45    else if (the_symbol == "CADJPY") {
 46      margin = margin / 22000;
 47    }
 48
 49    else if (the_symbol == "CHFJPY") {
 50      margin = margin / 20000;
 51    }
 52
 53    else if (the_symbol == "EURAUD") {
 54      margin = margin / 1000000;
 55    }
 56
 57    else if (the_symbol == "EURCAD") {
 58      margin = margin / 2000000;
 59    }
 60
 61    else if (the_symbol == "EURCHF") {
 62      margin = margin / 2500000;
 63    }
 64
 65    else if (the_symbol == "EURGBP") {
 66      margin = margin / 5000000;
 67    }
 68
 69    else if (the_symbol == "EURJPY") {
 70       margin = margin / 20000;
 71    }
 72
 73    else if (the_symbol == "EURUSD") {
 74      margin = margin / 2500000;
 75    }
 76
 77    else if (the_symbol == "GBPAUD") {
 78      margin = margin / 1000000;
 79    }
 80
 81    else if (the_symbol == "GBPCAD") {
 82      margin = margin / 1800000;
 83    }
 84
 85    else if (the_symbol == "GBPCHF") {
 86      margin = margin / 1800000;
 87    }
 88
 89    else if (the_symbol == "GBPJPY") {
 90      margin = margin / 14000;
 91    }
 92
 93    else if (the_symbol == "GBPUSD") {
 94      margin = margin / 1800000;
 95    }
 96
 97    else if (the_symbol == "USDCAD") {
 98      margin = margin / 3000000;
 99    }
100
101    else if (the_symbol == "USDCHF") {
102      margin = margin / 2200000;
103    }
104
105    else if (the_symbol == "USDJPY") {
106      margin = margin / 22000;
107    }
108
109    SetIndexBuffer(0, trade);
110    return(0);
111  }
112
113
114  int start() {
115
116    ac = iAC(symbol, timeframe, shift);
117    old_ac = iAC(symbol, timeframe, span - shift);
118
119    if (old_ac < 0 - margin && ac > 0 + margin ) {
120      trade[0] = 1;
121    }
122    else if (old_ac > 0 + margin && ac < 0 - margin) {
123      trade[0] = -1;
124    }
125    else {
126      trade[0] = 0;
127    }
128
129    return(0);
130  }

Switches are just like predictors, except that they return only two values: 1 or 0.

  1  // adx_gt_val.mq4
  2  // an Algocrowd switch
  3  #property indicator_chart_window
  4  
  5  
  6  extern string the_symbol;
  7  extern double val = 1; // INT 1-1000
  8  extern int period = 7; // INT 1-50
  9  extern int applied_price = PRICE_HIGH; // ENUM_APPLIED_PRICE
 10  extern int mode = MODE_MAIN; // ?
 11  extern int shift = 0; // INT 0-50
 12  extern int span = 1; // INT 1-49
 13
 14
 15  string symbol;
 16  int timeframe;
 17  
 18  
 19  double trade[];
 20
 21
 22  int init() {
 23
 24    if (the_symbol == "AUDCAD") {
 25      val = val / 9;
 26    }
 27
 28    else if (the_symbol == "AUDCHF") {
 29      val = val / 7;
 30    }
 31
 32    else if (the_symbol == "AUDJPY") {
 33      val = val / 7;
 34    }
 35
 36    else if (the_symbol == "AUDUSD") {
 37      val = val / 9;
 38    }
 39
 40    else if (the_symbol == "CADCHF") {
 41      val = val / 9;
 42    }
 43
 44    else if (the_symbol == "CADJPY") {
 45      val = val / 9;
 46    }
 47
 48    else if (the_symbol == "CHFJPY") {
 49      val = val / 9;
 50    }
 51
 52    else if (the_symbol == "EURAUD") {
 53      val = val / 9;
 54    }
 55
 56    else if (the_symbol == "EURCAD") {
 57      val = val / 9;
 58    }
 59
 60    else if (the_symbol == "EURCHF") {
 61      val = val / 9;
 62    }
 63
 64    else if (the_symbol == "EURGBP") {
 65      val = val / 9;
 66    }
 67
 68    else if (the_symbol == "EURJPY") {
 69      va = val / 9;
 70    }
 71
 72    else if (the_symbol == "EURUSD") {
 73      val = val / 9;
 74    }
 75
 76    else if (the_symbol == "GBPAUD") {
 77      val = val / 9;
 78    }
 79
 80    else if (the_symbol == "GBPCAD") {
 81      val = val / 9;
 82    }
 83
 84    else if (the_symbol == "GBPCHF") {
 85      val = val / 9;
 86    }
 87
 88    else if (the_symbol == "GBPJPY") {
 89      val = val / 9;
 90    }
 91
 92    else if (the_symbol == "GBPUSD") {
 93      val = val / 9;
 94    }
 95
 96    else if (the_symbol == "USDCAD") {
 97      val = val / 9;
 98    }
 99
100    else if (the_symbol == "USDCHF") {
101      val = val / 9;
102    }
103
104    else if (the_symbol == "USDJPY") {
105      val = val / 9;
106    }
107
108    SetIndexBuffer(0, trade);
109    return(0);
110  }
111
112
113  int start() {
114
115    if (iADX(symbol, timeframe, period, applied_price, mode, shift) > val) {
116      trade[0] = 1;
117    }
118    else {
119      trade[0] = 0;
120    }
121    return(0);
122  }

The following MQL4 functions can be used in Algocrowd indicators:

The following MQL4 constants can be used in Algocrowd indicators: