{ Volume Weighted MACD
  Copyright 2011, P.J.Kaufman. All rights reserved. }
  
  inputs: period1(12), period2(26), signalper(9);
  vars:	 avg1(0), avg2(0), signal(0), vwmacd(0), closevol(0);
  
  closevol = close*Volume;
  avg1 = summation(closevol,period1)/summation(volume,period1);
  avg2 = Summation(closevol,period2)/summation(volume,period2);
  vwmacd = avg1 - avg2;
  signal = average(vwmacd,signalper);
  
  plot1(vwmacd,"VWMACD");
  plot2(signal,"Signal");
  