function compute()
{
var masses = new Array(.001,1,.45359,1016,1000);
var bmasses = new Array(.001,1,.45359,1016,1000);
// Mass units into Kg

var grad = new Array(1,.3048,.9144);
// Metres / feet / Yards into Metres

var metresPerSec = new Array(.446944,.278,1)

// alert(metresPerSec[document.motcurr.units.selectedIndex])

var speed = document.motcurr.Ispeed.value * metresPerSec[document.motcurr.units.selectedIndex]

// OGross = Gross weight
var gross = (document.motcurr.Imass.value)*masses[document.motcurr.MassUnits.selectedIndex] + (document.motcurr.Iadult.value)*12*6.35 + (document.motcurr.Ichild.value)*5*6.35 + (document.motcurr.Ibatt.value)*bmasses[document.motcurr.BattMass.selectedIndex]*(document.motcurr.Ivolts.value)/12;
// 1 Stone=14 lbs=6.35kG
document.motcurr.Ogross.value=Math.round(gross*100)/100;

// alert(speed);
// alert(document.motcurr.Ispeed.value);
// alert(grad[document.motcurr.units.selectedIndex]);
// alert(document.motcurr.Igrad.value);
// alert(grad[document.motcurr.GradUnits.selectedIndex]);
// alert(gross)

// Oraise = speed of raising load
var vertSpd = speed * document.motcurr.Igrad.value / 100;
document.motcurr.Oraise.value=Math.round(vertSpd*100)/100;

// alert(vertSpd);

// OPower = current for climbing gradient
var power = gross * 9.81183 * vertSpd;
document.motcurr.Opower.value=Math.round(power*100)/100;
var peCurr = power/document.motcurr.Ivolts.value
document.motcurr.Mcurr.value=Math.round(peCurr*100)/100;

// KE 
var energy = gross * speed * speed /2
document.motcurr.KE.value = Math.round(energy*100)/100;
var keCurr = energy/document.motcurr.Iaccel.value / document.motcurr.Ivolts.value * 2;
document.motcurr.Acurr.value = Math.round(keCurr*100)/100;

// alert(document.motcurr.Ilevel.value)
// alert(peCurr)
// alert(keCurr)

document.motcurr.ttlAmps.value = Math.round((eval(document.motcurr.Ilevel.value) + peCurr + keCurr)*100)/100;

// Time to climb hill
document.motcurr.hillTime.value = Math.round(100*document.motcurr.Ileng.value * grad[document.motcurr.GradUnits.selectedIndex]/speed)/100;
document.motcurr.Oaccel.value = document.motcurr.Iaccel.value
}

function click() {       
  if (event.button==2) {       
     alert('·PÁ±zªº¥úÁ{.')       
    }       
  }       
  document.onmousedown=click