From b94e27229184632f14d534710e834186fea3572c Mon Sep 17 00:00:00 2001
From: Ray Speth <speth@mit.edu>
Date: Sat, 9 Apr 2016 00:18:34 -0400
Subject: [PATCH] [Numerics] Fix invalid memory access in DenseMatrix::mult

Results were incorrect for rectangular matrices
---
 src/numerics/DenseMatrix.cpp   |  2 +-
 test/general/test_matrices.cpp | 47 ++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/src/numerics/DenseMatrix.cpp b/src/numerics/DenseMatrix.cpp
index 6a200e930c..a716e349b3 100644
--- a/src/numerics/DenseMatrix.cpp
+++ b/src/numerics/DenseMatrix.cpp
@@ -87,7 +87,7 @@ void DenseMatrix::mult(const double* b, double* prod) const
 {
     ct_dgemv(ctlapack::ColMajor, ctlapack::NoTranspose,
              static_cast<int>(nRows()),
-             static_cast<int>(nRows()), 1.0, ptrColumn(0),
+             static_cast<int>(nColumns()), 1.0, ptrColumn(0),
              static_cast<int>(nRows()), b, 1, 0.0, prod, 1);
 }
 
diff --git a/test/general/test_matrices.cpp b/test/general/test_matrices.cpp
index 292ff74230..b7a140a7f0 100644
--- a/test/general/test_matrices.cpp
+++ b/test/general/test_matrices.cpp
@@ -1,5 +1,6 @@
 #include "gtest/gtest.h"
 #include "cantera/numerics/BandMatrix.h"
+#include "cantera/numerics/DenseMatrix.h"
 
 using namespace Cantera;
 
@@ -103,3 +104,49 @@ TEST_F(BandMatrixTest, checkRowsColumns) {
     EXPECT_EQ((size_t) 0, i);
     EXPECT_DOUBLE_EQ(1, s);
 }
+
+class DenseMatrixTest : public testing::Test
+{
+public:
+    DenseMatrixTest()
+        : x4{1,2,3,4}
+        , x3{3,2,1}
+        , b1{14, 32, 66, -34}
+        , b2{-6, 4, 26, 2}
+        , b3{14, 32, 66}
+    {
+        A1.resize(4, 4); // square
+        A2.resize(4, 3); // more rows
+        A3.resize(3, 4); // more columns
+
+        for (int i = 0; i < 3; i++) {
+            for (int j = 0; j < 3; j++) {
+                A1(i,j) = A2(i,j) = A3(i,j) = i*i + 2*j*j + i*j - 3;
+            }
+            A1(3,i) = A2(3,i) = pow(-1, i);
+            A1(i,3) = A3(i,3) = pow(2, i);
+        }
+        A1(3,3) = -9;
+    }
+
+    DenseMatrix A1, A2, A3;
+    vector_fp x4, x3;
+    vector_fp b1, b2, b3;
+};
+
+TEST_F(DenseMatrixTest, matrix_times_vector)
+{
+    vector_fp c(4, 0.0);
+    A1.mult(x4.data(), c.data());
+    for (size_t i = 0; i < 4; i++) {
+        EXPECT_DOUBLE_EQ(b1[i], c[i]);
+    }
+    A2.mult(x3.data(), c.data());
+    for (size_t i = 0; i < 4; i++) {
+        EXPECT_DOUBLE_EQ(b2[i], c[i]);
+    }
+    A3.mult(x4.data(), c.data());
+    for (size_t i = 0; i < 3; i++) {
+        EXPECT_DOUBLE_EQ(b3[i], c[i]);
+    }
+}