Updated some skipped unit tests that now work

unit-tests/matrix-tests.cpp

@@ -615,7 +615,6 @@ TEST_CASE("Eigenvalues and Vectors", "Matrix") {
   }
 
   SECTION("3x3 Rank Defficient Eigen") {
-    SKIP("Skipping this because QR decomposition isn't ready for it");
     // this symmetrix tridiagonal matrix is well behaved for testing
     Matrix<3, 3> A{1, 2, 3, 4, 5, 6, 7, 8, 9};
 
@@ -630,11 +629,13 @@ TEST_CASE("Eigenvalues and Vectors", "Matrix") {
     values.ToString(strBuf1);
     std::cout << "Values:\n" << strBuf1 << std::endl;
 
+    // EigenQR emits eigenvalues largest-magnitude first, so column 0 of the
+    // vectors is the eigenvector for the largest eigenvalue (16.1168).
     REQUIRE_THAT(vectors[0][0], Catch::Matchers::WithinRel(0.23197f, 1e-4f));
     REQUIRE_THAT(vectors[1][0], Catch::Matchers::WithinRel(0.525322f, 1e-4f));
     REQUIRE_THAT(vectors[2][0], Catch::Matchers::WithinRel(0.81867f, 1e-4f));
-    REQUIRE_THAT(values[0][0], Catch::Matchers::WithinRel(-1.11684f, 1e-4f));
-    REQUIRE_THAT(values[1][0], Catch::Matchers::WithinRel(0.0f, 1e-4f));
-    REQUIRE_THAT(values[2][0], Catch::Matchers::WithinRel(16.1168f, 1e-4f));
+    REQUIRE_THAT(values[0][0], Catch::Matchers::WithinRel(16.1168f, 1e-4f));
+    REQUIRE_THAT(values[1][0], Catch::Matchers::WithinRel(-1.11684f, 1e-4f));
+    REQUIRE_THAT(values[2][0], Catch::Matchers::WithinAbs(0.0f, 1e-6f));
   }
 }