/*  sdfsinhs.cpp  by K.Tsuru  */
// function ID 3308     DRADIX
/****************************************
SDouble class
sinh x by series |x| < DRADIX.
sinh x = x/1! + x^3/3! + x^5/5! + .....
*****************************************/
#ifndef SN_H
#include "sn.h"
#endif
static const char* func = "SinhSeries";
SDouble SinhSeries(const SDouble& x){
    if(x.NetRdxExp() > 1) x.SetError(x.OUT_OF_RANGE, func, 3308);

    SDouble sum(x), xsq, t, delta;
    sum.FixedPoint(sum.RdxExp());
    xsq = x*x;
    t = x*xsq;
    delta = DsDiv(t, 6);    // delta = x^3/6
    ulong n = 4uL, mt = sum.SlOpMaxValue(), den;
    sum = DDAdd(sum, delta);    //  sum += delta;

    while( delta.Sign(3308) ){
        den = n*(n+1uL);
        if(den >= mt) break;
        t = delta*xsq;
        delta = DsDiv(t, den);  //It can devide by n(n+1) once.
        sum = DDAdd(sum, delta);    //  sum += delta;
        n += 2uL;
    }

    while(delta.Sign(3308)){
        if(n >= mt){
            sum.SetError(sum.NOT_CONVERGE, func, -3308);
            break;
        }
        t = delta*xsq;
        delta = DsDiv(t, n);    delta = DsDiv(delta, n+1uL);    //twice
        sum = DDAdd(sum, delta);    //  sum += delta;
        n += 2;
    }
    sum.PointFree();
    sum.Reform(3308);
    sum.upToTerm = n/2;
    return sum;
}