<!-- Author: Brian Mackenzie -->
<!-- Date: 11th March 2004 -->
<!-- Version: 1.0 -->

<!-- Function:  Calculate energy expenditure   -->

<!-- Required by: energyexp.htm -->

<!-- Copyright Brian Mackenzie 2004 -->


function calculate()

{
  var cals = eval(document.stride.exercise.options[document.stride.exercise.selectedIndex].value);
  var time = document.stride.time.value;
  var weight = document.stride.weight.value;

  //number of calores based on time
  cals = cals * (time/30);

  //every 7kg above or below 68k add or subtract 10%
  ext = (weight - 68) / 70;
  cals = cals + (cals * ext);

  document.stride.calories.value = nt2dp(cals,0);

}

function valclear()
{
  document.stride.calories.value = "";
}

function nt2dp(num,dp)
{
<!-- rounds num to dp decimal places -->
  num=num*1+(0.55/Math.pow(10,dp));
  if (dp>0) dp=dp+1;
  b=Math.floor(num).toString().length+dp;
  return num.toString().substr(0,b);
}