1 files changed, 29 insertions, 0 deletions

diff --git a/src/lib/src/matrix.c b/src/lib/src/matrix.c
index a7a4ce6..29cdec5 100644
--- a/src/lib/src/matrix.c
+++ b/src/lib/src/matrix.c
@@ -150,6 +150,35 @@ void nnMatrixMul(const nnMatrix* left, const nnMatrix* right, nnMatrix* out) {
   }
 }
 
+void nnMatrixMulRows(const nnMatrix* left, const nnMatrix* right, nnMatrix* out) {
+  assert(left != 0);
+  assert(right != 0);
+  assert(out != 0);
+  assert(out != left);
+  assert(out != right);
+  assert(left->cols == right->cols);
+  assert(out->rows == left->rows);
+  assert(out->cols == right->rows);
+
+  R* out_value = out->values;
+
+  for (int i = 0; i < left->rows; ++i) {
+    const R* left_row = &left->values[i * left->cols];
+    const R* right_value = right->values;
+
+    for (int j = 0; j < right->rows; ++j) {
+      *out_value = 0;
+
+      // Vector dot product.
+      for (int k = 0; k < left->cols; ++k) {
+        *out_value += left_row[k] * *right_value++;
+      }
+
+      out_value++;
+    }
+  }
+}
+
 void nnMatrixMulAdd(const nnMatrix* left, const nnMatrix* right, R scale, nnMatrix* out) {
   assert(left);
   assert(right);