function vypocitat(form) {

// koeficienty

var koef = new Array();

koef['do25'] = [
//  0%  10%    20%    30%    40%    50%   
[1.154, 1.150, 1.127, 1.094, 1.086, 1.084],
[1.228, 1.226, 1.187, 1.150, 1.136, 1.116],
[1.310, 1.290, 1.239, 1.213, 1.190, 1.170],
[1.419, 1.410, 1.322, 1.248, 1.223, 1.183],
[1.601, 1.597, 1.360, 1.314, 1.274, 1.254],
[1.649, 1.617, 1.519, 1.456, 1.400, 1.350],
[1.888, 1.825, 1.692, 1.603, 1.559, 1.493],
[2.087, 1.985, 1.815, 1.700, 1.602, 1.519]
];

koef['25-50'] = [
//  0%  10%    20%    30%    40%    50%   
[1.105, 1.096, 1.087, 1.078, 1.070, 1.061],
[1.158, 1.144, 1.130, 1.116, 1.101, 1.087],
[1.227, 1.206, 1.185, 1.164, 1.143, 1.122],
[1.300, 1.272, 1.244, 1.216, 1.186, 1.158],
[1.418, 1.377, 1.337, 1.297, 1.257, 1.217],
[1.505, 1.456, 1.407, 1.358, 1.309, 1.260],
[1.688, 1.621, 1.554, 1.486, 1.419, 1.352],
[1.820, 1.738, 1.658, 1.578, 1.498, 1.418]
];

koef['nad50'] = [
//  0%  10%    20%    30%    40%    50%   
[1.099, 1.090, 1.081, 1.072, 1.064, 1.055],
[1.152, 1.138, 1.124, 1.110, 1.095, 1.081],
[1.221, 1.200, 1.179, 1.158, 1.137, 1.116],
[1.294, 1.266, 1.238, 1.210, 1.180, 1.152],
[1.412, 1.371, 1.331, 1.291, 1.251, 1.211],
[1.499, 1.450, 1.401, 1.352, 1.303, 1.254],
[1.682, 1.615, 1.548, 1.480, 1.413, 1.346],
[1.814, 1.732, 1.652, 1.572, 1.492, 1.412] 
];

koef['delayed'] = [
//  0%  10%    20%    30%    40%    50%   
  [0, 1.260, 1.212, 1.182, 1.165, 1.148],
  [0, 1.292, 1.241, 1.199, 1.177, 1.157],
  [0, 1.358, 1.302, 1.259, 1.230, 1.202],
  [0, 1.494, 1.389, 1.298, 1.267, 1.221],
  [0, 1.689, 1.432, 1.366, 1.319, 1.292],
  [0, 1.713, 1.593, 1.508, 1.445, 1.387],
  [0, 1.931, 1.772, 1.657, 1.603, 1.528],
  [0, 2.102, 1.900, 1.755, 1.647, 1.554]
];

var rpm = new Array();

rpm['do25'] = [
//  0%  10%    20%    30%    40%    50%   
[33.17, 36.77, 35.48, 29.94, 32.72, 40.05],
[27.95, 31.66, 30.10, 28.08, 30.61, 32.27],
[24.11, 25.85, 24.70, 25.99, 28.08, 31.61],
[23.36, 26.38, 24.34, 22.18, 24.28, 24.87],
[20.71, 23.95, 17.44, 18.18, 19.43, 23.09],
[18.14, 20.19, 20.40, 21.86, 24.05, 27.59],
[17.22, 19.06, 19.60, 21.25, 25.56, 31.00],
[15.85, 17.39, 17.91, 19.42, 21.76, 25.86]
];

rpm['25-50'] = [
//  0%  10%    20%    30%    40%    50%   
[22.10, 22.73, 23.47, 24.39, 25.97, 27.67],
[19.25, 19.82, 20.48, 21.28, 22.03, 23.29],
[17.78, 18.34, 18.97, 19.70, 20.57, 21.67],
[17.05, 17.68, 18.38, 19.20, 19.94, 21.07],
[14.99, 15.61, 16.34, 17.17, 18.14, 19.29],
[14.60, 15.32, 16.14, 17.06, 18.13, 19.41],
[13.98, 14.87, 15.89, 17.05, 18.46, 20.19],
[12.72, 13.62, 14.69, 15.97, 17.53, 19.50]
];

rpm['nad50'] = [
//  0%  10%    20%    30%    40%    50%   
[20.78, 21.22, 21.74, 22.35, 23.53, 24.64],
[18.51, 18.97, 19.49, 20.10, 20.61, 21.51],
[17.32, 17.80, 18.34, 18.94, 19.64, 20.50],
[16.72, 17.29, 17.93, 18.64, 19.24, 20.18],
[14.80, 15.38, 16.06, 16.82, 17.68, 18.69],
[14.45, 15.14, 15.91, 16.77, 17.76, 18.90],
[13.88, 14.74, 15.73, 16.83, 18.17, 19.78],
[12.65, 13.52, 14.57, 15.80, 17.30, 19.15]
];

rpm['delayed'] = [
//  0%  10%    20%    30%    40%    50%   
[0, 68.35, 63.80, 64.35, 71.35, 81.55],
[0, 41.48, 39.61, 38.37, 41.37, 46.22],
[0, 31.95, 31.51, 32.10, 34.82, 38.78],
[0, 31.62, 29.50, 26.93, 29.64, 30.95],
[0, 27.32, 20.85, 21.29, 22.92, 27.20],
[0, 22.99, 23.21, 24.45, 27.13, 31.28],
[0, 21.14, 21.73, 23.24, 27.96, 34.14],
[0, 19.09, 19.64, 21.01, 23.70, 28.36]
];

var mes = new Array(6, 10, 15, 20, 30, 36, 48, 60);
                
// je zadana cena?
var cena = form.moca.value;
if (isNaN(cena)) {
  alert('Prosím zadajte predajnú cenu tovaru!');
  return;       
}               

if (cena>50000.010) {
  var ctype='nad50';
} else if (cena<50000.005 && cena>25000.01) {
  var ctype='25-50';
} else if (cena<25000.005) {
  var ctype='do25';
}

if (form.odlozenie.checked) {
  var ctype='delayed';
}

var doba = form.dlzka.options[form.dlzka.selectedIndex].value;
var akont = form.akontacia.options[form.akontacia.selectedIndex].value;
var rocnam = rpm[ctype][doba][akont];
var koeficient = koef[ctype][doba][akont];
var mesiace = mes[doba];
var perc = akont*10;

//pri odlozenej splatnosti nemoze byt nulova akontacia
if (ctype == 'delayed' && perc == 0) {
  alert("Pri 3 mesačnej odloženej splatnosti nie je nulová akontácia povolená!");
  return;
}

var suma = Math.ceil(cena*koeficient);
var akontacia = suma * perc / 100;
var splatka = suma - akontacia;
var splatka = (perc == 0) ? Math.round(splatka / mesiace) : Math.floor(splatka / mesiace);
var celkom = splatka * mesiace;
var akontacia = (perc==0) ? 0 : suma - celkom;
	 
form.suma.value = suma;
form.akont.value = akontacia;
form.splatka.value = splatka; 
form.miera.value = rocnam;
}