// RETURNS A SCALE FACTOR TO MULTIPLY THE COEFFICIENTS OF THE POLYNOMIAL.
// THE SCALING IS DONE TO AVOID OVERFLOW AND TO AVOID UNDETECTED UNDERFLOW
// INTERFERING WITH THE CONVERGENCE CRITERION. THE FACTOR IS A POWER OF THE
//int BASE.
// PT - MODULUS OF COEFFICIENTS OF P
// ETA, INFIN, SMALNO, BASE - CONSTANTS DESCRIBING THE FLOATING POINT ARITHMETIC.
//
static void scale(const int deg, xcomplex* P)
{
int hi, lo, max, min, x, sc;
// Find largest and smallest moduli of coefficients
hi = (int)(xdata.MAX_EXP / 2.0);
lo = (int)(xdata.MIN_EXP - xbits(P[0]));
max = xlogb(P[0]); // leading coefficient does not vanish!
min = xlogb(P[0]);
for(int i = 0; i <= deg; i++) {
if (P[i] != xdata.ZERO){
x = xlogb(P[i]);
if(x > max) max = x;
if(x < min) min = x;
}
}
// Scale only if there are very large or very small components
if(min >= lo && max <= hi) return;
x = lo - min;
if(x <= 0)
sc = -(max+min) / 2;
else {
sc = x;
if(xdata.MAX_EXP - sc > max) sc = 0;
}
// Scale the polynomial
for(int i = 0; i<= deg; i++){ xscalbln(&P[i],sc); }
}
movword(void)
{
int w;
Tchar i, *wp;
int savwch, hys;
over = 0;
wp = wordp;
if (!nwd) {
while (cbits(*wp++) == ' ') {
wch--;
wne -= sps;
}
wp--;
}
if (wne > nel && !hyoff && hyf && (!nwd || nel > 3 * sps) &&
(!(hyf & 02) || (findt1() > lss)))
hyphen(wp);
savwch = wch;
hyp = hyptr;
nhyp = 0;
while (*hyp && *hyp <= wp)
hyp++;
while (wch) {
if (hyoff != 1 && *hyp == wp) {
hyp++;
if (!wdstart || (wp > wdstart + 1 && wp < wdend &&
(!(hyf & 04) || wp < wdend - 1) && /* 04 => last 2 */
(!(hyf & 010) || wp > wdstart + 2))) { /* 010 => 1st 2 */
nhyp++;
storeline((Tchar)IMP, 0);
}
}
i = *wp++;
w = width(i);
wne -= w;
wch--;
storeline(i, w);
}
if (nel >= 0) {
nwd++;
return(0); /* line didn't fill up */
}
if (TROFF)
xbits((Tchar)HYPHEN, 1);
hys = width((Tchar)HYPHEN);
m1:
if (!nhyp) {
if (!nwd)
goto m3;
if (wch == savwch)
goto m4;
}
if (*--linep != IMP)
goto m5;
if (!(--nhyp))
if (!nwd)
goto m2;
if (nel < hys) {
nc--;
goto m1;
}
m2:
if ((i = cbits(*(linep - 1))) != '-' && i != EMDASH) {
*linep = (*(linep - 1) & SFMASK) | HYPHEN;
w = width(*linep);
nel -= w;
ne += w;
linep++;
}
m3:
nwd++;
m4:
wordp = wp;
return(1); /* line filled up */
m5:
nc--;
w = width(*linep);
ne -= w;
nel += w;
wne += w;
wch++;
wp--;
goto m1;
}
