From 16c2500a9993878aead5a1c33762d71edbe44ee9 Mon Sep 17 00:00:00 2001
From: Richard Roberts <richard.jw.roberts@gmail.com>
Date: Fri, 23 Sep 2011 15:34:57 +0000
Subject: [PATCH] Bug fix and unit tests for Permutation, documentation fixes

---
 gtsam/inference/Permutation.cpp           |   4 +-
 gtsam/inference/Permutation.h             |  24 +++---
 gtsam/inference/tests/testPermutation.cpp | 100 ++++++++++++++++++++++
 3 files changed, 112 insertions(+), 16 deletions(-)
 create mode 100644 gtsam/inference/tests/testPermutation.cpp

diff --git a/gtsam/inference/Permutation.cpp b/gtsam/inference/Permutation.cpp
index 781ebb30a..f162df712 100644
--- a/gtsam/inference/Permutation.cpp
+++ b/gtsam/inference/Permutation.cpp
@@ -45,7 +45,7 @@ Permutation Permutation::PullToFront(const vector<Index>& toFront, size_t size,
 
   // Put the pulled variables at the front of the permutation and set up the
   // pulled flags.
-  size_t toFrontUniqueSize;
+  size_t toFrontUniqueSize = 0;
   for(Index j=0; j<toFront.size(); ++j) {
     if(!pulled[toFront[j]]) {
       ret[j] = toFront[j];
@@ -148,7 +148,7 @@ Permutation::shared_ptr Permutation::inverse() const {
 
 /* ************************************************************************* */
 void Permutation::print(const std::string& str) const {
-  std::cout << str;
+  std::cout << str << " ";
   BOOST_FOREACH(Index s, rangeIndices_) { std::cout << s << " "; }
   std::cout << std::endl;
 }
diff --git a/gtsam/inference/Permutation.h b/gtsam/inference/Permutation.h
index 4974d22b7..75149718f 100644
--- a/gtsam/inference/Permutation.h
+++ b/gtsam/inference/Permutation.h
@@ -116,19 +116,7 @@ public:
   bool equals(const Permutation& rhs, double tol=0.0) const { return rangeIndices_ == rhs.rangeIndices_; }
 
   /**
-   * Syntactic sugar for accessing another container through a permutation.
-   * Allows the syntax:
-   *   Permuted<Container> permuted(permutation, container);
-   *   permuted[index1];
-   *   permuted[index2];
-   * which is equivalent to:
-   *   container[permutation[index1]];
-   *   container[permutation[index2]];
-   * but more concise.
-   */
-
-  /**
-   * Permute the permutation, p1.permute(p2)[i] is equivalent to p2[p1[i]].
+   * Permute the permutation, p1.permute(p2)[i] is equivalent to p1[p2[i]].
    */
   Permutation::shared_ptr permute(const Permutation& permutation) const;
 
@@ -154,7 +142,15 @@ protected:
 
 
 /**
- * Definition of Permuted class, see above comment for details.
+ * Syntactic sugar for accessing another container through a permutation.
+ * Allows the syntax:
+ *   Permuted<Container> permuted(permutation, container);
+ *   permuted[index1];
+ *   permuted[index2];
+ * which is equivalent to:
+ *   container[permutation[index1]];
+ *   container[permutation[index2]];
+ * but more concise.
  */
 template<typename CONTAINER, typename VALUETYPE = typename CONTAINER::value_reference_type>
 class Permuted {
diff --git a/gtsam/inference/tests/testPermutation.cpp b/gtsam/inference/tests/testPermutation.cpp
new file mode 100644
index 000000000..a6c5116b5
--- /dev/null
+++ b/gtsam/inference/tests/testPermutation.cpp
@@ -0,0 +1,100 @@
+/*
+ * testPermutation.cpp
+ *
+ *  Created on: Sep 22, 2011
+ *      Author: richard
+ */
+
+#include <CppUnitLite/TestHarness.h>
+
+#include <gtsam/base/Testable.h>
+#include <gtsam/inference/Permutation.h>
+
+#include <vector>
+
+using namespace gtsam;
+using namespace std;
+
+TEST(Permutation, Identity) {
+  Permutation expected(5);
+  expected[0] = 0;
+  expected[1] = 1;
+  expected[2] = 2;
+  expected[3] = 3;
+  expected[4] = 4;
+
+  Permutation actual = Permutation::Identity(5);
+
+  EXPECT(assert_equal(expected, actual));
+}
+
+TEST(Permutation, PullToFront) {
+  Permutation expected(5);
+  expected[0] = 4;
+  expected[1] = 0;
+  expected[2] = 2;
+  expected[3] = 1;
+  expected[4] = 3;
+
+  std::vector<Index> toFront;
+  toFront.push_back(4);
+  toFront.push_back(0);
+  toFront.push_back(2);
+  Permutation actual = Permutation::PullToFront(toFront, 5);
+
+  EXPECT(assert_equal(expected, actual));
+}
+
+TEST(Permutation, PushToBack) {
+  Permutation expected(5);
+  expected[0] = 1;
+  expected[1] = 3;
+  expected[2] = 4;
+  expected[3] = 0;
+  expected[4] = 2;
+
+  std::vector<Index> toBack;
+  toBack.push_back(4);
+  toBack.push_back(0);
+  toBack.push_back(2);
+  Permutation actual = Permutation::PushToBack(toBack, 5);
+
+  EXPECT(assert_equal(expected, actual));
+}
+
+TEST(Permutation, compose) {
+  Permutation p1(5);
+  p1[0] = 1;
+  p1[1] = 2;
+  p1[2] = 3;
+  p1[3] = 4;
+  p1[4] = 0;
+
+  Permutation p2(5);
+  p2[0] = 1;
+  p2[1] = 2;
+  p2[2] = 4;
+  p2[3] = 3;
+  p2[4] = 0;
+
+  Permutation expected(5);
+  expected[0] = 2;
+  expected[1] = 4;
+  expected[2] = 3;
+  expected[3] = 0;
+  expected[4] = 1;
+
+  Permutation actual = *p2.permute(p1);
+
+  EXPECT(assert_equal(expected, actual));
+  LONGS_EQUAL(p2[p1[0]], actual[0]);
+  LONGS_EQUAL(p2[p1[1]], actual[1]);
+  LONGS_EQUAL(p2[p1[2]], actual[2]);
+  LONGS_EQUAL(p2[p1[3]], actual[3]);
+  LONGS_EQUAL(p2[p1[4]], actual[4]);
+}
+
+/* ************************************************************************* */
+int main() {  TestResult tr;  return TestRegistry::runAllTests(tr); }
+
+