1 files changed, 102 insertions, 0 deletions
diff --git a/test/inverse.cpp b/test/inverse.cpp
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+++ b/test/inverse.cpp
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+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
+// Copyright (C) 2008 Benoit Jacob <jacob.benoit.1@gmail.com>
+//
+// 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
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include "main.h"
+#include <Eigen/LU>
+
+template<typename MatrixType> void inverse(const MatrixType& m)
+{
+  typedef typename MatrixType::Index Index;
+  /* this test covers the following files:
+     Inverse.h
+  */
+  Index rows = m.rows();
+  Index cols = m.cols();
+
+  typedef typename MatrixType::Scalar Scalar;
+  typedef typename NumTraits<Scalar>::Real RealScalar;
+  typedef Matrix<Scalar, MatrixType::ColsAtCompileTime, 1> VectorType;
+
+  MatrixType m1(rows, cols),
+             m2(rows, cols),
+             identity = MatrixType::Identity(rows, rows);
+  createRandomPIMatrixOfRank(rows,rows,rows,m1);
+  m2 = m1.inverse();
+  VERIFY_IS_APPROX(m1, m2.inverse() );
+
+  VERIFY_IS_APPROX((Scalar(2)*m2).inverse(), m2.inverse()*Scalar(0.5));
+
+  VERIFY_IS_APPROX(identity, m1.inverse() * m1 );
+  VERIFY_IS_APPROX(identity, m1 * m1.inverse() );
+
+  VERIFY_IS_APPROX(m1, m1.inverse().inverse() );
+
+  // since for the general case we implement separately row-major and col-major, test that
+  VERIFY_IS_APPROX(MatrixType(m1.transpose().inverse()), MatrixType(m1.inverse().transpose()));
+
+#if !defined(EIGEN_TEST_PART_5) && !defined(EIGEN_TEST_PART_6)
+  //computeInverseAndDetWithCheck tests
+  //First: an invertible matrix
+  bool invertible;
+  RealScalar det;
+
+  m2.setZero();
+  m1.computeInverseAndDetWithCheck(m2, det, invertible);
+  VERIFY(invertible);
+  VERIFY_IS_APPROX(identity, m1*m2);
+  VERIFY_IS_APPROX(det, m1.determinant());
+
+  m2.setZero();
+  m1.computeInverseWithCheck(m2, invertible);
+  VERIFY(invertible);
+  VERIFY_IS_APPROX(identity, m1*m2);
+
+  //Second: a rank one matrix (not invertible, except for 1x1 matrices)
+  VectorType v3 = VectorType::Random(rows);
+  MatrixType m3 = v3*v3.transpose(), m4(rows,cols);
+  m3.computeInverseAndDetWithCheck(m4, det, invertible);
+  VERIFY( rows==1 ? invertible : !invertible );
+  VERIFY_IS_MUCH_SMALLER_THAN(internal::abs(det-m3.determinant()), RealScalar(1));
+  m3.computeInverseWithCheck(m4, invertible);
+  VERIFY( rows==1 ? invertible : !invertible );
+#endif
+
+  // check in-place inversion
+  if(MatrixType::RowsAtCompileTime>=2 && MatrixType::RowsAtCompileTime<=4)
+  {
+    // in-place is forbidden
+    VERIFY_RAISES_ASSERT(m1 = m1.inverse());
+  }
+  else
+  {
+    m2 = m1.inverse();
+    m1 = m1.inverse();
+    VERIFY_IS_APPROX(m1,m2);
+  }
+}
+
+void test_inverse()
+{
+  int s;
+  for(int i = 0; i < g_repeat; i++) {
+    CALL_SUBTEST_1( inverse(Matrix<double,1,1>()) );
+    CALL_SUBTEST_2( inverse(Matrix2d()) );
+    CALL_SUBTEST_3( inverse(Matrix3f()) );
+    CALL_SUBTEST_4( inverse(Matrix4f()) );
+    CALL_SUBTEST_4( inverse(Matrix<float,4,4,DontAlign>()) );
+    s = internal::random<int>(50,320);
+    CALL_SUBTEST_5( inverse(MatrixXf(s,s)) );
+    s = internal::random<int>(25,100);
+    CALL_SUBTEST_6( inverse(MatrixXcd(s,s)) );
+    CALL_SUBTEST_7( inverse(Matrix4d()) );
+    CALL_SUBTEST_7( inverse(Matrix<double,4,4,DontAlign>()) );
+  }
+  EIGEN_UNUSED_VARIABLE(s)
+}