How to calculate house cusps

I have used below formulas of placidus system to get house cusps but am not getting correct cusp. Is any step missing or something else need to be done? What is the correct way to get accurate cusp for Niryan bhav chalit chart?



function CuspPlacidus(RA, OB,LA, deg, FF, fNeg)
{
var LO, R1, XS, X;
var i;
var rPi = 3.14159265358979323846;

R1 = RA + deg;
X = fNeg ? -1.0 : 1.0;

/* Looping 10 times is arbitrary, but it's what other programs do. */
for (i = 1; i <= 10; i++) {

/* This formula works except at 0 latitude (AA == 0.0). */

XS = (X * Math.sin(R1) * Math.tan(OB) * Math.tan(LA == 0.0 ? 0.0001 : LA)) % 360.0;
XS = arcctg(XS);
if (XS < 0.0)
XS += rPi;
R1 = RA + (fNeg ? rPi-(XS/FF) : (XS/FF));
}
LO = Math.atan(Math.tan(R1)/Math.cos(OB));
if (LO < 0.0)
LO += rPi;
if (Math.sin(R1) < 0.0)
LO += rPi;

return radToDeg(LO);
}

var tempra = degToRad((((6.6460656 + 2400.0512617 * t + 2.581e-5 * t * t + f) * 15 + ln) % 360)); //RAMC
var tempob = degToRad((23.452294 - 0.0130125 * t - 0.00000164 * t*t + 0.000000503 *t*t*t )); //Ecliptic
var mc = radToDeg(Math.atan(tan(ra),cos(ob)));// Midheaven
var as = radToDeg(arcctg(-((tan(la * d2r)*sin(ob)) + (sin(ra)*cos(ob)))/cos(ra))); //Ascendent

var chouse = new Array(12);
chouse[1] = as;
chouse[2] = CuspPlacidus(tempra,tempob,degToRad(la),degToRad(120.0), 1.5, true)
chouse[3] = CuspPlacidus(tempra,tempob,degToRad(la),degToRad(150.0), 3.0, true)
chouse[4] = mc + 180;
chouse[5] = CuspPlacidus(tempra,tempob,degToRad(la),degToRad(30.0), 3.0, false) + 180.0;
chouse[6] = CuspPlacidus(tempra,tempob,degToRad(la),degToRad(60.0), 1.5, false) + 180.0;