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36 #include "gmx_lapack.h"
37 #include "lapack_limits.h"
39 #include <types/simple.h>
42 F77_FUNC(dlasq6,DLASQ6)(int *i0,
60 const double safemin = GMX_DOUBLE_MIN*(1.0+GMX_DOUBLE_EPS);
64 if (*n0 - *i0 - 1 <= 0) {
68 j4 = (*i0 << 2) + *pp - 3;
75 for (j4 = *i0*4; j4 <= i__1; j4 += 4) {
76 z__[j4 - 2] = d__ + z__[j4 - 1];
77 if (fabs(z__[j4 - 2])<GMX_DOUBLE_MIN) {
82 } else if (safemin * z__[j4 + 1] < z__[j4 - 2] && safemin * z__[j4
84 temp = z__[j4 + 1] / z__[j4 - 2];
85 z__[j4] = z__[j4 - 1] * temp;
88 z__[j4] = z__[j4 + 1] * (z__[j4 - 1] / z__[j4 - 2]);
89 d__ = z__[j4 + 1] * (d__ / z__[j4 - 2]);
94 d__1 = emin, d__2 = z__[j4];
95 emin = (d__1<d__2) ? d__1 : d__2;
99 for (j4 = *i0 << 2; j4 <= i__1; j4 += 4) {
100 z__[j4 - 3] = d__ + z__[j4];
101 if (fabs(z__[j4 - 3])<GMX_DOUBLE_MIN) {
106 } else if (safemin * z__[j4 + 2] < z__[j4 - 3] && safemin * z__[j4
107 - 3] < z__[j4 + 2]) {
108 temp = z__[j4 + 2] / z__[j4 - 3];
109 z__[j4 - 1] = z__[j4] * temp;
112 z__[j4 - 1] = z__[j4 + 2] * (z__[j4] / z__[j4 - 3]);
113 d__ = z__[j4 + 2] * (d__ / z__[j4 - 3]);
117 d__1 = emin, d__2 = z__[j4 - 1];
118 emin = (d__1<d__2) ? d__1 : d__2;
124 j4 = 4*(*n0 - 2) - *pp;
125 j4p2 = j4 + (*pp << 1) - 1;
126 z__[j4 - 2] = *dnm2 + z__[j4p2];
127 if (fabs(z__[j4 - 2])<GMX_DOUBLE_MIN) {
129 *dnm1 = z__[j4p2 + 2];
132 } else if (safemin * z__[j4p2 + 2] < z__[j4 - 2] && safemin * z__[j4 - 2] <
134 temp = z__[j4p2 + 2] / z__[j4 - 2];
135 z__[j4] = z__[j4p2] * temp;
136 *dnm1 = *dnm2 * temp;
138 z__[j4] = z__[j4p2 + 2] * (z__[j4p2] / z__[j4 - 2]);
139 *dnm1 = z__[j4p2 + 2] * (*dnm2 / z__[j4 - 2]);
146 j4p2 = j4 + (*pp << 1) - 1;
147 z__[j4 - 2] = *dnm1 + z__[j4p2];
148 if (fabs(z__[j4 - 2])<GMX_DOUBLE_MIN) {
153 } else if (safemin * z__[j4p2 + 2] < z__[j4 - 2] && safemin * z__[j4 - 2] <
155 temp = z__[j4p2 + 2] / z__[j4 - 2];
156 z__[j4] = z__[j4p2] * temp;
159 z__[j4] = z__[j4p2 + 2] * (z__[j4p2] / z__[j4 - 2]);
160 *dn = z__[j4p2 + 2] * (*dnm1 / z__[j4 - 2]);
166 z__[(*n0 << 2) - *pp] = emin;