void NR::mpdiv(Vec_O_UCHR &q, Vec_O_UCHR &r, Vec_I_UCHR &u, Vec_I_UCHR &v)
{
const int MACC=1;
int i,is,mm;
int n=u.size();
int m=v.size();
int p=r.size();
int n_min=MIN(m,p);
if (m > n) nrerror("Divisor longer than dividend in mpdiv");
mm=m+MACC;
Vec_UCHR s(mm),rr(mm),ss(mm+1),qq(n-m+1),t(n);
mpinv(s,v);
mpmul(rr,s,u);
mpsad(ss,rr,1);
mplsh(ss);
mplsh(ss);
mpmov(qq,ss);
mpmov(q,qq);
mpmul(t,qq,v);
mplsh(t);
mpsub(is,t,u,t);
if (is != 0) nrerror("MACC too small in mpdiv");
for (i=0;i<n_min;i++) r[i]=t[i+n-m];
if (p>m)
for (i=m;i<p;i++) r[i]=0;
}
void mpsqrt(unsigned char w[], unsigned char u[], unsigned char v[], int n,
int m)
{
void mplsh(unsigned char u[], int n);
void mpmov(unsigned char u[], unsigned char v[], int n);
void mpmul(unsigned char w[], unsigned char u[], unsigned char v[], int n,
int m);
void mpneg(unsigned char u[], int n);
void mpsdv(unsigned char w[], unsigned char u[], int n, int iv, int *ir);
int i,ir,j,mm;
float fu,fv;
unsigned char *r,*s;
r=cvector(1,n<<1);
s=cvector(1,n<<1);
mm=IMIN(m,MF);
fv=(float) v[mm];
for (j=mm-1;j>=1;j--) {
fv *= BI;
fv += v[j];
}
fu=1.0/sqrt(fv);
for (j=1;j<=n;j++) {
i=(int) fu;
u[j]=(unsigned char) i;
fu=256.0*(fu-i);
}
for (;;) {
mpmul(r,u,u,n,n);
mplsh(r,n);
mpmul(s,r,v,n,IMIN(m,n));
mplsh(s,n);
mpneg(s,n);
s[1] -= 253;
mpsdv(s,s,n,2,&ir);
for (j=2;j<n;j++) {
if (s[j]) {
mpmul(r,s,u,n,n);
mpmov(u,&r[1],n);
break;
}
}
if (j<n) continue;
mpmul(r,u,v,n,IMIN(m,n));
mpmov(w,&r[1],n);
free_cvector(s,1,n<<1);
free_cvector(r,1,n<<1);
return;
}
}
void mpinv(unsigned char u[], unsigned char v[], int n, int m)
{
void mpmov(unsigned char u[], unsigned char v[], int n);
void mpmul(unsigned char w[], unsigned char u[], unsigned char v[], int n,
int m);
void mpneg(unsigned char u[], int n);
unsigned char *rr,*s;
int i,j,maxmn,mm;
float fu,fv;
maxmn=IMAX(n,m);
rr=cvector(1,1+(maxmn<<1));
s=cvector(1,maxmn);
mm=IMIN(MF,m);
fv=(float) v[mm];
for (j=mm-1;j>=1;j--) {
fv *= BI;
fv += v[j];
}
fu=1.0/fv;
for (j=1;j<=n;j++) {
i=(int) fu;
u[j]=(unsigned char) i;
fu=256.0*(fu-i);
}
for (;;) {
mpmul(rr,u,v,n,m);
mpmov(s,&rr[1],n);
mpneg(s,n);
s[1] -= 254;
mpmul(rr,s,u,n,n);
mpmov(u,&rr[1],n);
for (j=2;j<n;j++)
if (s[j]) break;
if (j==n) {
free_cvector(s,1,maxmn);
free_cvector(rr,1,1+(maxmn<<1));
return;
}
}
}
