function calculatePivot()
    {
        if(!isNaN(document.getElementById('high').value) && !isNaN(document.getElementById('low').value) 
            && !isNaN(document.getElementById('close').value)
            && document.getElementById('high').value != '' && document.getElementById('low').value != '' 
            && document.getElementById('close').value != '')
        {
            document.getElementById('error').innerHTML = '';
            var high = parseFloat(document.getElementById('high').value);
            var low = parseFloat(document.getElementById('low').value);
            var close = parseFloat(document.getElementById('close').value);                        
                        
            var pivot = (high + low + close)/3;
            var r3 =    high + 2*(pivot - low);
            var r1 =    2*pivot - low;
            var s3 =    low - 2*(high - pivot);
            var s1 =    2 * pivot - high;
            var r2 =    pivot + (r1 - s1)                
            var s2 =    pivot - (r1 - s1)                                             
                
            document.getElementById('r3').value = Math.round(r3*10000)/10000;
            document.getElementById('r2').value = Math.round(r2*10000)/10000;
            document.getElementById('r1').value = Math.round(r1*10000)/10000;
            document.getElementById('pivot').value = Math.round(pivot*10000)/10000;
            document.getElementById('s3').value = Math.round(s3*10000)/10000;
            document.getElementById('s2').value = Math.round(s2*10000)/10000;
            document.getElementById('s1').value = Math.round(s1*10000)/10000;            
        }                            
        
        
        else
        {                    
            document.getElementById('error').innerHTML = 'Illegal  input';
        }
    }