VPA Relative Vol for Amibroker (AFL)

_SECTION_BEGIN("VPA_Relative_Vol");
LBP = Param("Look Back", 15, 0, 100,1 );
V1=IIf(V<=0,MA(V,LBP),V);  //minimize errors on volume data (data <= 0)
Mean = MA(ln(V1),LBP);     // LBP periods moving average of(natural logaritm of( volume))
avvol = exp(mean);         // average volume
VolUnit = avvol/3.5;       // avvol=VolUnit*3.5
// color up bar volume blue, down bar volume red, volume lower than the volumes of the 2 previous bars pink
Clr = IIf(V1<Ref(V1,-1)AND V1<Ref(V1,-2),11,IIf(Close>Ref(Close,-1),29,IIf(Close==Ref(Close,-1),1,32)));

                                    //   Ultra High band 
                                    //   Ultra High band 
                                    //   Ultra High band 
VeryHighBand = avvol + VolUnit*3.5;// 7 ----------------
                                    //   Very High band  
HighBand = avvol + VolUnit*2.5;    // 6 ----------------
                                    //   High band       
                                    //   High band       
AvgBandHigh = avvol + VolUnit/2;   // 4 ----------------
//------------------------------------ 3.5 Average band
AvgBandLow = avvol - VolUnit/2;    // 3 ----------------
                                    //   Low band
                                    //   Low band
LowBand = avvol - VolUnit*2.5;     // 1 ----------------
                                    //   Very low band  
//-------------------------------------0-----------------
Plot(exp(ln(V1)),"",Clr,6); // plot Volume Histogram
Plot(avvol,"",29,1);// plot average volume
Plot(0,"",29,1|4096); // plot 0 volume
Plot(LowBand,"",40,styleArea|1|4096);
Plot(AvgBandLow,"",52,styleArea|1|4096);
Plot(AvgBandHigh,"",10,styleArea|1|4096);
Plot(HighBand,"",52,styleArea|1|4096);
Plot(VeryHighBand,"",40,styleArea|1|4096);

_SECTION_END();