Multiply by 10, then do your rounding, then divide by 10 again
(Math.round(12.362 * 10) / 10).toFixed(2)
Another option is:
Number(12.362.toFixed(1)).toFixed(2)
In your code:
var panel;
if (routeNodes.length > 0 && (panel = document.getElementById('distance')))
{
panel.innerHTML = Number((dist/1609.344).toFixed(1)).toFixed(2)
+ " miles = £"
+ Number((((dist/1609.344 - 1) * 1.20) + 2.80).toFixed(1)).toFixed(2);
}
To declare a minimum, use the Math.max
function:
var a = 10.1, b = 2.2, c = 3.5;
alert(Math.max(a, 2.8)); // alerts 10.1 (a);
alert(Math.max(b, 2.8)); // alerts 2.8 because it is larger than b (2.2);
alert(Math.max(c, 2.8)); // alerts 3.5 (c);