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39 #include <types/simple.h>
43 F77_FUNC(dsyr2k,DSYR2K)(const char *uplo,
68 double alpha = *alpha__;
69 double beta = *beta__;
72 ch2 = toupper(*trans);
79 if(n==0 || ( ( fabs(alpha)<GMX_DOUBLE_MIN || k==0 ) && fabs(beta-1.0)<GMX_DOUBLE_EPS))
82 if(fabs(alpha)<GMX_DOUBLE_MIN ) {
84 if(fabs(beta)<GMX_DOUBLE_MIN)
87 c[(j-1)*(ldc)+(i-1)] = 0.0;
91 c[(j-1)*(ldc)+(i-1)] *= beta;
94 if(fabs(beta)<GMX_DOUBLE_MIN)
97 c[(j-1)*(ldc)+(i-1)] = 0.0;
101 c[(j-1)*(ldc)+(i-1)] *= beta;
109 if(fabs(beta)<GMX_DOUBLE_MIN)
111 c[(j-1)*(ldc)+(i-1)] = 0.0;
112 else if(fabs(beta-1.0)>GMX_DOUBLE_EPS)
114 c[(j-1)*(ldc)+(i-1)] *= beta;
116 if( fabs(a[(l-1)*(lda)+(j-1)])>GMX_DOUBLE_MIN ||
117 fabs(b[(l-1)*(ldb)+(j-1)])>GMX_DOUBLE_MIN) {
118 temp1 = alpha * b[(l-1)*(ldb)+(j-1)];
119 temp2 = alpha * a[(l-1)*(lda)+(j-1)];
121 c[(j-1)*(ldc)+(i-1)] +=
122 a[(l-1)*(lda)+(i-1)] * temp1 +
123 b[(l-1)*(ldb)+(i-1)] * temp2;
130 if(fabs(beta)<GMX_DOUBLE_MIN)
132 c[(j-1)*(ldc)+(i-1)] = 0.0;
133 else if(fabs(beta-1.0)>GMX_DOUBLE_EPS)
135 c[(j-1)*(ldc)+(i-1)] *= beta;
137 if( fabs(a[(l-1)*(lda)+(j-1)])>GMX_DOUBLE_MIN ||
138 fabs(b[(l-1)*(ldb)+(j-1)])>GMX_DOUBLE_MIN) {
139 temp1 = alpha * b[(l-1)*(ldb)+(j-1)];
140 temp2 = alpha * a[(l-1)*(lda)+(j-1)];
142 c[(j-1)*(ldc)+(i-1)] +=
143 a[(l-1)*(lda)+(i-1)] * temp1 +
144 b[(l-1)*(ldb)+(i-1)] * temp2;
157 temp1 += a[(i-1)*(lda)+(l-1)] * b[(j-1)*(ldb)+(l-1)];
158 temp2 += b[(i-1)*(ldb)+(l-1)] * a[(j-1)*(lda)+(l-1)];
160 if(fabs(beta)<GMX_DOUBLE_MIN)
161 c[(j-1)*(ldc)+(i-1)] = alpha * (temp1 + temp2);
163 c[(j-1)*(ldc)+(i-1)] = beta * c[(j-1)*(ldc)+(i-1)] +
164 alpha * (temp1 + temp2);
173 temp1 += a[(i-1)*(lda)+(l-1)] * b[(j-1)*(ldb)+(l-1)];
174 temp2 += b[(i-1)*(ldb)+(l-1)] * a[(j-1)*(lda)+(l-1)];
176 if(fabs(beta)<GMX_DOUBLE_MIN)
177 c[(j-1)*(ldc)+(i-1)] = alpha * (temp1 + temp2);
179 c[(j-1)*(ldc)+(i-1)] = beta * c[(j-1)*(ldc)+(i-1)] +
180 alpha * (temp1 + temp2);