function convert(temperature)
{
	var error_msg = '<p>Please enter a number</p>';

	if (temperature == "F")
	{
		C =  (212-32)/100 * document.convert_temp.celsius.value + 32;
		if(isNaN(C))
		{
			document.getElementById('temperature_error').style.display = 'block';
			document.getElementById('temperature_error').innerHTML  = error_msg;
			document.convert_temp.reset();
		}
		else
		{
			document.getElementById('temperature_error').style.display = 'none';
			document.convert_temp.fahrenheit.value = Math.round(C*100)/100;
		}
	}
	else 
	{
		F = 100/(212-32) * (document.convert_temp.fahrenheit.value - 32);
		if(isNaN(F))
		{
			document.getElementById('temperature_error').style.display = 'block';
			document.getElementById('temperature_error').innerHTML  = error_msg;
			document.convert_temp.reset();
		}
		else
		{		
			document.getElementById('temperature_error').style.display = 'none';
			document.convert_temp.celsius.value = Math.round(F*100)/100;
		}
	}
}