1 /*
  2  *   Copyright (c) 2009, Michael Lehn
  3  *
  4  *   All rights reserved.
  5  *
  6  *   Redistribution and use in source and binary forms, with or without
  7  *   modification, are permitted provided that the following conditions
  8  *   are met:
  9  *
 10  *   1) Redistributions of source code must retain the above copyright
 11  *      notice, this list of conditions and the following disclaimer.
 12  *   2) Redistributions in binary form must reproduce the above copyright
 13  *      notice, this list of conditions and the following disclaimer in
 14  *      the documentation and/or other materials provided with the
 15  *      distribution.
 16  *   3) Neither the name of the FLENS development group nor the names of
 17  *      its contributors may be used to endorse or promote products derived
 18  *      from this software without specific prior written permission.
 19  *
 20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 23  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 24  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 25  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 26  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 27  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 28  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 29  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 30  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 31  */
 32 
 33 #ifndef CXXBLAS_LEVEL2_HER_TCC
 34 #define CXXBLAS_LEVEL2_HER_TCC 1
 35 
 36 #include <complex>
 37 #include <cxxblas/level1/level1.h>
 38 
 39 namespace cxxblas {
 40 
 41 template <typename IndexType, typename ALPHA, typename VX, typename MA>
 42 void
 43 her_generic(StorageOrder order, StorageUpLo upLo,  Transpose conjugateA,
 44             IndexType n,
 45             const ALPHA &alpha,
 46             const VX *x, IndexType incX,
 47             MA *A, IndexType ldA)
 48 {
 49     if (alpha==ALPHA(0)) {
 50         return;
 51     }
 52     if (order==ColMajor) {
 53         upLo = (upLo==Upper) ? Lower : Upper;
 54         conjugateA = Transpose(conjugateA^Conj);
 55     }
 56     #ifdef CXXBLAS_USE_XERBLA
 57         // insert error check here
 58     #endif
 59     if (upLo==Upper) {
 60         if (conjugateA==Conj) {
 61             for (IndexType i=0, iX=0; i<n; ++i, iX+=incX) {
 62                 axpy_generic(n-i, alpha*conjugate(x[iX]),
 63                                   x+iX, incX,
 64                                   A+i*(ldA+1), IndexType(1));
 65             }
 66         } else {
 67             for (IndexType i=0, iX=0; i<n; ++i, iX+=incX) {
 68                 acxpy_generic(n-i, alpha*x[iX],
 69                                    x+iX, incX,
 70                                    A+i*(ldA+1), IndexType(1));
 71             }
 72         }
 73     } else {
 74         if (conjugateA==Conj) {
 75             for (IndexType i=0, iX=0; i<n; ++i, iX+=incX) {
 76                 axpy_generic(i+1, alpha*conjugate(x[iX]),
 77                                   x, incX,
 78                                   A+i*ldA, IndexType(1));
 79             }
 80         } else {
 81             for (IndexType i=0, iX=0; i<n; ++i, iX+=incX) {
 82                 acxpy_generic(i+1, alpha*x[iX],
 83                                    x, incX,
 84                                    A+i*ldA, IndexType(1));
 85             }
 86         }
 87     }
 88     for (IndexType i=0; i<n; ++i) {
 89         A[i*ldA+i] = cxxblas::real(A[i*ldA+i]);
 90     }
 91 }
 92 
 93 template <typename IndexType, typename ALPHA, typename VX, typename MA>
 94 void
 95 her(StorageOrder order, StorageUpLo upLo,
 96     IndexType n,
 97     const ALPHA &alpha,
 98     const VX *x, IndexType incX,
 99     MA *A, IndexType ldA)
100 {
101     CXXBLAS_DEBUG_OUT("her_generic");
102 
103     if (incX<0) {
104         x -= incX*(n-1);
105     }
106     her_generic(order, upLo, NoTrans, n, alpha, x, incX, A, ldA);
107 }
108 
109 // namespace cxxblas
110 
111 #endif // CXXBLAS_LEVEL2_HER_TCC