BLAS: implement DSDOT and SDSDOT; update test for them.

1 files changed, 17 insertions, 0 deletions

diff --git a/blas/single.cpp b/blas/single.cpp
index 1b7775aed..d549a906e 100644
--- a/blas/single.cpp
+++ b/blas/single.cpp
@@ -2,6 +2,7 @@
 // for linear algebra.
 //
 // Copyright (C) 2009 Gael Guennebaud <gael.guennebaud@inria.fr>
+// Copyright (C) 2012 Chen-Pang He <jdh8@ms63.hinet.net>
 //
 // This Source Code Form is subject to the terms of the Mozilla
 // Public License v. 2.0. If a copy of the MPL was not distributed
@@ -17,3 +18,19 @@
 #include "level2_impl.h"
 #include "level2_real_impl.h"
 #include "level3_impl.h"
+
+float BLASFUNC(sdsdot)(int* n, float* alpha, float* px, int* incx, float* py, int* incy)
+{
+  float* x = reinterpret_cast<float*>(px);
+  float* y = reinterpret_cast<float*>(py);
+  float ret = *alpha;
+
+  if(*n>0) {
+    if(*incx==1 && *incy==1)    ret += (vector(x,*n).cwiseProduct(vector(y,*n))).sum();
+    else if(*incx>0 && *incy>0) ret += (vector(x,*n,*incx).cwiseProduct(vector(y,*n,*incy))).sum();
+    else if(*incx<0 && *incy>0) ret += (vector(x,*n,-*incx).reverse().cwiseProduct(vector(y,*n,*incy))).sum();
+    else if(*incx>0 && *incy<0) ret += (vector(x,*n,*incx).cwiseProduct(vector(y,*n,-*incy).reverse())).sum();
+    else if(*incx<0 && *incy<0) ret += (vector(x,*n,-*incx).reverse().cwiseProduct(vector(y,*n,-*incy).reverse())).sum();
+  }
+  return ret;
+}