function getParameters() {
  var parstring=window.location.search;
  if (parstring != null) {
   parstring=parstring.substring(1,parstring.length);
   arrayOfParVal = parstring.split('&');
   for (var i=0; i < arrayOfParVal.length; i++) {
     arrayOfPar=arrayOfParVal[i].split('=');
     if (arrayOfPar[0]=='P0') {P0=arrayOfPar[1]}
     if (arrayOfPar[0]=='P1') {P1=arrayOfPar[1]}
     if (arrayOfPar[0]=='P2') {P2=arrayOfPar[1]}
     if (arrayOfPar[0]=='P12') {P12=arrayOfPar[1]}
     if (arrayOfPar[0]=='P15') {P15=arrayOfPar[1]}
     if (arrayOfPar[0]=='P16') {P16=arrayOfPar[1]}
     if (arrayOfPar[0]=='P17') {P17=arrayOfPar[1]}
     if (arrayOfPar[0]=='P18') {
        P18=arrayOfPar[1]
        arrayOfParVal = P18.split('+');
        P18='';
        for (var i=0; i < arrayOfParVal.length; i++) {
        P18=P18 + arrayOfParVal[i] + ' ';}
        }
   }
  }
 }