/* Celsius / Fahrenheit functions */
function celsius_to_fahrenheit() {
  if (!checkDigitsSpecial(document.getElementById("celsius"), 'Celsius', 1, '.-')) {
    document.getElementById("celsius").value = '0.0';
    return; 
    }
  var Fahrenheit = ((document.getElementById("celsius").value * 9 / 5) + 32);
  document.getElementById("fahrenheit").value = Fahrenheit.toFixed(1);
  }
  
function fahrenheit_to_celsius() {
  if (!checkDigitsSpecial(document.getElementById("fahrenheit"), 'Fahrenheit', 1, '.-')) {
    document.getElementById("fahrenheit").value = '0.0';
    return;
    }
  var Celsius = (((document.getElementById("fahrenheit").value) - 32) * 5 / 9);
  document.getElementById("celsius").value = Celsius.toFixed(1);
  }
  
function reset_temperatures() {
  document.getElementById("celsius").value = '0.0';
  document.getElementById("fahrenheit").value = '32.0';
  }

/* Liters / Gallons functions */
function liters_to_gallons() {
  if (!checkDigitsSpecial(document.getElementById("liters"), 'Liters', 1, '.')) {
    document.getElementById("liters").value = '0.00';
    return; 
    }
  var Gallons = (document.getElementById("liters").value / 3.785);
  document.getElementById("gallons").value = Gallons.toFixed(2);
  }
  
function gallons_to_liters() {
  if (!checkDigitsSpecial(document.getElementById("gallons"), 'Gallons', 1, '.')) {
    document.getElementById("gallons").value = '0.00';
    return;
    }
  var Liters = (document.getElementById("gallons").value * 3.785);
  document.getElementById("liters").value = Liters.toFixed(2);
  }

function reset_volumes() {
  document.getElementById("liters").value = '0.00';
  document.getElementById("gallons").value = '0.00';
  }

/* Kilometers / Miles functions */
function kilometers_to_miles() {
  if (!checkDigitsSpecial(document.getElementById("kilometers"), 'Kilometers', 1, '.')) {
    document.getElementById("kilometers").value = '0.00';
    return; 
    }
    
  var Miles = (document.getElementById("kilometers").value / 1.609);
  document.getElementById("miles").value = Miles.toFixed(2);
  }
  
function miles_to_kilometers() {
  if (!checkDigitsSpecial(document.getElementById("miles"), 'Miles', 1, '.')) {
    document.getElementById("Miles").value = '0.00';
    return;
    }
    
  var Kilometers = (document.getElementById("miles").value * 1.609);
  document.getElementById("kilometers").value = Kilometers.toFixed(2);
  }
  
function reset_distances() {
  document.getElementById("kilometers").value = '0.00';
  document.getElementById("miles").value = '0.00';
  }

/* Kilometers per Liters / Miles per Gallons functions */
function kilometers_per_liter_to_miles_per_gallon() {
  if (!checkDigitsSpecial(document.getElementById("kilometers_per_liter"), 'Kilometers Per Liter', 1, '.')) {
    document.getElementById("kilometers_per_liter").value = '0.00';
    return; 
    }
    
  var Miles_Per_Gallon = (document.getElementById("kilometers_per_liter").value / 0.425);
  document.getElementById("miles_per_gallon").value = Miles_Per_Gallon.toFixed(2);
  }
  
function miles_per_gallon_to_kilometers_per_liter() {
  if (!checkDigitsSpecial(document.getElementById("miles_per_gallon"), 'Miles Per Gallon', 1, '.')) {
    document.getElementById("miles_per_gallon").value = '0.00';
    return;
    }
    
  var Kilometers_Per_Liter = (document.getElementById("miles_per_gallon").value * 0.425);
  document.getElementById("kilometers_per_liter").value = Kilometers_Per_Liter.toFixed(2);
  }
  
function reset_milage() {
  document.getElementById("kilometers_per_liter").value = '0.00';
  document.getElementById("miles_per_gallon").value = '0.00';
  }