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38 #include <types/simple.h>
42 F77_FUNC(ssyr2k,SSYR2K)(const char *uplo,
66 float alpha = *alpha__;
70 ch2 = toupper(*trans);
77 if(n==0 || ( ( fabs(alpha)<GMX_FLOAT_MIN || k==0 ) && fabs(beta-1.0)<GMX_FLOAT_EPS))
80 if(fabs(alpha)<GMX_FLOAT_MIN) {
82 if(fabs(beta)<GMX_FLOAT_MIN)
85 c[(j-1)*(ldc)+(i-1)] = 0.0;
89 c[(j-1)*(ldc)+(i-1)] *= beta;
92 if(fabs(beta)<GMX_FLOAT_MIN)
95 c[(j-1)*(ldc)+(i-1)] = 0.0;
99 c[(j-1)*(ldc)+(i-1)] *= beta;
107 if(fabs(beta)<GMX_FLOAT_MIN)
109 c[(j-1)*(ldc)+(i-1)] = 0.0;
110 else if(fabs(beta-1.0)>GMX_FLOAT_EPS)
112 c[(j-1)*(ldc)+(i-1)] *= beta;
114 if( fabs(a[(l-1)*(lda)+(j-1)])>GMX_FLOAT_MIN ||
115 fabs(b[(l-1)*(ldb)+(j-1)])>GMX_FLOAT_MIN) {
116 temp1 = alpha * b[(l-1)*(ldb)+(j-1)];
117 temp2 = alpha * a[(l-1)*(lda)+(j-1)];
119 c[(j-1)*(ldc)+(i-1)] +=
120 a[(l-1)*(lda)+(i-1)] * temp1 +
121 b[(l-1)*(ldb)+(i-1)] * temp2;
128 if(fabs(beta)<GMX_FLOAT_MIN)
130 c[(j-1)*(ldc)+(i-1)] = 0.0;
131 else if(fabs(beta-1.0)>GMX_FLOAT_EPS)
133 c[(j-1)*(ldc)+(i-1)] *= beta;
135 if( fabs(a[(l-1)*(lda)+(j-1)])>GMX_FLOAT_MIN ||
136 fabs(b[(l-1)*(ldb)+(j-1)])>GMX_FLOAT_MIN) {
137 temp1 = alpha * b[(l-1)*(ldb)+(j-1)];
138 temp2 = alpha * a[(l-1)*(lda)+(j-1)];
140 c[(j-1)*(ldc)+(i-1)] +=
141 a[(l-1)*(lda)+(i-1)] * temp1 +
142 b[(l-1)*(ldb)+(i-1)] * temp2;
155 temp1 += a[(i-1)*(lda)+(l-1)] * b[(j-1)*(ldb)+(l-1)];
156 temp2 += b[(i-1)*(ldb)+(l-1)] * a[(j-1)*(lda)+(l-1)];
158 if(fabs(beta)<GMX_FLOAT_MIN)
159 c[(j-1)*(ldc)+(i-1)] = alpha * (temp1 + temp2);
161 c[(j-1)*(ldc)+(i-1)] = beta * c[(j-1)*(ldc)+(i-1)] +
162 alpha * (temp1 + temp2);
171 temp1 += a[(i-1)*(lda)+(l-1)] * b[(j-1)*(ldb)+(l-1)];
172 temp2 += b[(i-1)*(ldb)+(l-1)] * a[(j-1)*(lda)+(l-1)];
174 if(fabs(beta)<GMX_FLOAT_MIN)
175 c[(j-1)*(ldc)+(i-1)] = alpha * (temp1 + temp2);
177 c[(j-1)*(ldc)+(i-1)] = beta * c[(j-1)*(ldc)+(i-1)] +
178 alpha * (temp1 + temp2);