Merge pull request #78 from wolfv/fix_inv_single_el

Fix inverse on 1x1 matrix
xtensor-stack · Aug 11, 2018 · 693b3e4 · 693b3e4
2 parents 161d74b + cbef1d6
commit 693b3e4
Show file tree

Hide file tree

Showing 6 changed files with 123 additions and 59 deletions.
diff --git a/include/xtensor-blas/xblas.hpp b/include/xtensor-blas/xblas.hpp
@@ -42,7 +42,7 @@ namespace blas
         cxxblas::asum<blas_index_t>(
             static_cast<blas_index_t>(ad.shape()[0]),
             ad.data() + ad.data_offset(),
-            static_cast<blas_index_t>(ad.strides().front()),
+            stride_front(ad),
             result
         );
     }
@@ -62,7 +62,7 @@ namespace blas
         cxxblas::nrm2<blas_index_t>(
             static_cast<blas_index_t>(ad.shape()[0]),
             ad.data() + ad.data_offset(),
-            static_cast<blas_index_t>(ad.strides().front()),
+            stride_front(ad),
             result
         );
     }
@@ -86,9 +86,9 @@ namespace blas
         cxxblas::dot<blas_index_t>(
             static_cast<blas_index_t>(ad.shape()[0]),
             ad.data() + ad.data_offset(),
-            static_cast<blas_index_t>(ad.strides().front()),
+            stride_front(ad),
             bd.data() + bd.data_offset(),
-            static_cast<blas_index_t>(bd.strides().front()),
+            stride_front(bd),
             result
         );
     }
@@ -111,9 +111,9 @@ namespace blas
         cxxblas::dotu<blas_index_t>(
             static_cast<blas_index_t>(ad.shape()[0]),
             ad.data() + ad.data_offset(),
-            static_cast<blas_index_t>(ad.strides().front()),
+            stride_front(ad),
             bd.data() + bd.data_offset(),
-            static_cast<blas_index_t>(bd.strides().front()),
+            stride_front(bd),
             result
         );
     }

diff --git a/include/xtensor-blas/xblas_utils.hpp b/include/xtensor-blas/xblas_utils.hpp
@@ -128,6 +128,40 @@ namespace xt
         DEFAULT_LEADING_STRIDE_BEHAVIOR;
     }
 
+    /********************
+     * Get front stride *
+     ********************/
+
+    template <class E>
+    inline blas_index_t stride_front(const E& e)
+    {
+        if (E::static_layout == layout_type::column_major)
+        {
+            return blas_index_t(1);
+        }
+        else
+        {
+            return static_cast<blas_index_t>(e.strides().front() == 0 ? 1 : e.strides().front());
+        }
+    }
+
+    /*******************
+     * Get back stride *
+     *******************/
+
+    template <class E>
+    inline blas_index_t stride_back(const E& e)
+    {
+        if (E::static_layout == layout_type::row_major)
+        {
+            return blas_index_t(1);
+        }
+        else
+        {
+            return static_cast<blas_index_t>(e.strides().back() == 0 ? 1 : e.strides().back());
+        }
+    }
+
     /*******************************
      * is_xfunction implementation *
      *******************************/