int count_vec(const spiro_seg *s, int nseg)
{
int i;
int n = 0;
for (i = 0; i < nseg; i++)
n += compute_jinc(s[i].ty, s[i + 1].ty);
return n;
}
static double
spiro_iter(spiro_seg *s, bandmat *m, int *perm, double *v, int n, int nmat)
{
int cyclic, i, j, jthl, jthr, jk0l, jk0r, jk1l, jk1r, jk2l, jk2r, jinc, jj, k, n_invert;
char ty0, ty1;
double dk, norm, th;
double ends[2][4];
double derivs[4][2][4];
cyclic = s[0].ty != '{' && s[0].ty != 'v';
for (i = 0; i < nmat; i++) {
v[i] = 0.;
for (j = 0; j < 11; j++)
m[i].a[j] = 0.;
for (j = 0; j < 5; j++)
m[i].al[j] = 0.;
}
j = 0;
if (s[0].ty == 'o')
jj = nmat - 2;
else if (s[0].ty == 'c')
jj = nmat - 1;
else
jj = 0;
for (i = 0; i < n; i++) {
ty0 = s[i].ty;
ty1 = s[i + 1].ty;
jinc = compute_jinc(ty0, ty1);
th = s[i].bend_th;
jthl = jk0l = jk1l = jk2l = -1;
jthr = jk0r = jk1r = jk2r = -1;
compute_pderivs(&s[i], ends, derivs, jinc);
/* constraints crossing left */
if (ty0 == 'o' || ty0 == 'c' || ty0 == '[' || ty0 == ']' || \
ty0 == 'a' || ty0 == 'h') {
jthl = jj++;
jj %= nmat;
jk0l = jj++;
if (ty0 == 'o') {
jj %= nmat;
jk1l = jj++;
jk2l = jj++;
}
}
/* constraints on left */
if ((ty0 == '[' || ty0 == 'v' || ty0 == '{' || ty0 == 'c' || \
ty0 == 'a') && jinc == 4) {
if (ty0 != 'c')
jk1l = jj++;
jk2l = jj++;
}
/* constraints on right */
if ((ty1 == ']' || ty1 == 'v' || ty1 == '}' || ty1 == 'c' || \
ty1 == 'h') && jinc == 4) {
if (ty1 != 'c')
jk1r = jj++;
jk2r = jj++;
}
/* constraints crossing right */
if (ty1 == 'o' || ty1 == 'c' || ty1 == '[' || ty1 == ']' || \
ty1 == 'a' || ty1 == 'h') {
jthr = jj;
jk0r = (jj + 1) % nmat;
if (ty1 == 'o') {
jk1r = (jj + 2) % nmat;
jk2r = (jj + 3) % nmat;
}
}
add_mat_line(m, v, derivs[0][0], th - ends[0][0], 1, j, jthl, jinc, nmat);
add_mat_line(m, v, derivs[1][0], ends[0][1], -1, j, jk0l, jinc, nmat);
add_mat_line(m, v, derivs[2][0], ends[0][2], -1, j, jk1l, jinc, nmat);
add_mat_line(m, v, derivs[3][0], ends[0][3], -1, j, jk2l, jinc, nmat);
add_mat_line(m, v, derivs[0][1], -ends[1][0], 1, j, jthr, jinc, nmat);
add_mat_line(m, v, derivs[1][1], -ends[1][1], 1, j, jk0r, jinc, nmat);
add_mat_line(m, v, derivs[2][1], -ends[1][2], 1, j, jk1r, jinc, nmat);
add_mat_line(m, v, derivs[3][1], -ends[1][3], 1, j, jk2r, jinc, nmat);
if (jthl >= 0)
v[jthl] = mod_2pi(v[jthl]);
if (jthr >= 0)
v[jthr] = mod_2pi(v[jthr]);
j += jinc;
}
if (cyclic) {
memcpy(m + nmat, m, sizeof(bandmat) * nmat);
memcpy(m + 2 * nmat, m, sizeof(bandmat) * nmat);
memcpy(v + nmat, v, sizeof(double) * nmat);
memcpy(v + 2 * nmat, v, sizeof(double) * nmat);
n_invert = 3 * nmat;
j = nmat;
#ifdef VERBOSE
printf("cyclic\n");
#endif
} else {
n_invert = nmat;
j = 0;
}
#ifdef VERBOSE
for (i = 0; i < n; i++) {
for (k = 0; k < 11; k++)
printf(" %2.4f", m[i].a[k]);
printf(": %2.4f\n", v[i]);
}
printf("---\n");
#endif
bandec11(m, perm, n_invert);
banbks11(m, perm, v, n_invert);
norm = 0.;
for (i = 0; i < n; i++) {
jinc = compute_jinc(s[i].ty, s[i + 1].ty);
for (k = 0; k < jinc; k++) {
dk = v[j++];
#ifdef VERBOSE
printf("s[%d].ks[%d] += %f\n", i, k, dk);
#endif
s[i].ks[k] += dk;
norm += dk * dk;
}
s[i].ks[0] = 2.0 * mod_2pi(s[i].ks[0]/2.0);
}
return norm;
}