var MASSID = 1;
var LENGTHID = 2;
var TEMPERATUREID = 3;


var units_mass = [
  ["carats (metric)",                         0.0002],
  ["cental",                                  45.359237],
  ["Earth masses",                            5.980e24],
  ["grains",                                  0.00006479891],
  ["grams",                                   1e-3],
  ["hundredweights",                          50.80234544],
  ["kilograms [kg]",                          1],
  ["ounces (US & UK)",                    0.028349523125],
  ["ounces (troy, precious metals)",          0.0311034768],
  ["pounds [lbs] (US & UK)",              0.45359237],
  ["pounds (troy, precious metals)",          0.3732417216],
  ["Solar masses",                            1.989e30],
  ["slugs (g-pounds)",                        14.593903],
  ["stones",                                  6.35029318],
  ["tons (UK or long)",                       1016.0469088],
  ["tons (US or short)",                      907.18474],
  ["tonnes",                                  1000]
];

var units_length = [
  ["ångströms [Å]",                1e-10],
  ["astronomical units [AU]",         149598550000],
  ["barleycorns",                     0.008467],
  ["cables",                          182.88],
  ["centimeters [cm]",                0.01],
  ["chains (surveyors')",             20.116840233680467360934721869444],
  ["decimeters",                      0.1],
  ["ells (UK)",                       0.875],
  ["ems (pica)",                      0.0042333],
  ["fathoms",                         1.8288],
  ["feet (UK and US)",                0.3048],
  ["feet (US survey)",                0.30480060960121920243840487680975],
  ["furlongs",                        201.168],
  ["hands",                           0.1016],
  ["hectometers [hm]",                100],
  ["inches [in]",                     0.0254],
  ["kilometers [km]",                 1000],
  ["light years",                     9.460528405e15],
  ["meters [m]",                      1],
  ["micrometers [µm]",                1e-6],
  ["mil",                             0.0000254],
  ["miles (UK and US)",               1609.344],
  ["miles (nautical, international)", 1852],
  ["miles (nautical, UK)",            1853.184],
  ["millimeters [mm]",                0.001],
  ["nanometers [nm]",                 1e-9],
  ["parsecs",                         3.0856776e16],
  ["picometers",                      1e-12],
  ["yards",                           0.9144]
];

var units_temperature = [
  ["Celsius",    'value + 273.15',         'value - 273.15'],
  ["Fahrenheit", '5/9 * (value + 459.67)', '9/5 * value - 459.67'],
  ["Kelvin",     1],
  ["Rankine",    '5/9 * value',            '9/5 * value'],
  ["Réaumure",   '5/4 * value + 273.15',   '4/5 * (value - 273.15)']
];