gtsam/base/tests/testBTree.cpp

/*
 * testBTree.cpp
 *
 *  Created on: Feb 3, 2010
 *  @Author: Chris Beall
 *  @Author: Frank Dellaert
 */

#include <boost/shared_ptr.hpp>
#include <boost/foreach.hpp>
#include <boost/assign/std/list.hpp> // for +=
using namespace boost::assign;

#include <gtsam/CppUnitLite/TestHarness.h>
#include <gtsam/base/BTree.h>

using namespace std;
using namespace gtsam;

typedef pair<size_t, size_t> Range;
typedef BTree<string, Range> RangeTree;
typedef BTree<string, int> IntTree;

static std::stringstream ss;
static string x1("x1"), x2("x2"), x3("x3"), x4("x4"), x5("x5");
typedef pair<string, int> KeyInt;
KeyInt p1(x1, 1), p2(x2, 2), p3(x3, 3), p4(x4, 4), p5(x5, 5);

/* ************************************************************************* */
int f(const string& key, const Range& range) {
	return range.first;
}

void g(const string& key, int i) {
	ss << (string) key;
}

int add(const string& k, int v, int a) {
	return v + a;
}

/* ************************************************************************* */
TEST( BTree, add )
{
	RangeTree tree;
	CHECK(tree.empty())
	LONGS_EQUAL(0,tree.height())

	// check the height of tree after adding an element
	RangeTree tree1 = tree.add(x1, Range(1, 1));
	LONGS_EQUAL(1,tree1.height())
	LONGS_EQUAL(1,tree1.size())
	CHECK(tree1.find(x1) == Range(1,1))

	RangeTree tree2 = tree1.add(x5, Range(5, 2));
	RangeTree tree3 = tree2.add(x3, Range(3, 3));
	LONGS_EQUAL(3,tree3.size())
	CHECK(tree3.find(x5) == Range(5,2))
	CHECK(tree3.find(x3) == Range(3,3))

	RangeTree tree4 = tree3.add(x2, Range(2, 4));
	RangeTree tree5 = tree4.add(x4, Range(4, 5));
	LONGS_EQUAL(5,tree5.size())
	CHECK(tree5.find(x4) == Range(4,5))

	// Test functional nature: tree5 and tree6 have different values for x4
	RangeTree tree6 = tree5.add(x4, Range(6, 6));
	CHECK(tree5.find(x4) == Range(4,5))
	CHECK(tree6.find(x4) == Range(6,6))

	// test assignment
	RangeTree c5 = tree5;
	LONGS_EQUAL(5,c5.size())
	CHECK(c5.find(x4) == Range(4,5))

	// test map
	// After (map f tree5) tree contains (x1,1), (x2,2), etc...
	IntTree mapped = tree5.map<int> (f);
	LONGS_EQUAL(2,mapped.find(x2));
	LONGS_EQUAL(4,mapped.find(x4));
}

/* ************************************************************************* */
TEST( BTree, equality )
{
	IntTree tree1 = IntTree().add(p1).add(p2).add(p3).add(p4).add(p5);
	CHECK(tree1==tree1)
	CHECK(tree1.same(tree1))

	IntTree tree2 = IntTree().add(p1).add(p2).add(p3).add(p4).add(p5);
	CHECK(tree2==tree1)
	CHECK(!tree2.same(tree1))

	IntTree tree3 = IntTree().add(p1).add(p2).add(p3).add(p4);
	CHECK(tree3!=tree1)
	CHECK(tree3!=tree2)
	CHECK(!tree3.same(tree1))
	CHECK(!tree3.same(tree2))

	IntTree tree4 = tree3.add(p5);
	CHECK(tree4==tree1)
	CHECK(!tree4.same(tree1))

	IntTree tree5 = tree1;
	CHECK(tree5==tree1)
	CHECK(tree5==tree2)
	CHECK(tree5.same(tree1))
	CHECK(!tree5.same(tree2))
}

/* ************************************************************************* */
TEST( BTree, iterating )
{
	IntTree tree = IntTree().add(p1).add(p2).add(p3).add(p4).add(p5);

	// test iter
	tree.iter(g);
	CHECK(ss.str() == string("x1x2x3x4x5"));

	// test fold
	LONGS_EQUAL(25,tree.fold<int>(add,10))

	// test iterator
	BTree<string, int>::const_iterator it = tree.begin(), it2 = tree.begin();
	CHECK(it==it2)
	CHECK(*it == p1)
	CHECK(it->first == x1)
	CHECK(it->second == 1)
	CHECK(*(++it) == p2)
	CHECK(it!=it2)
	CHECK(it==(++it2))
	CHECK(*(++it) == p3)
	CHECK(*(it++) == p3)
	// post-increment, not so efficient
	CHECK(*it == p4)
	CHECK(*(++it) == p5)
	CHECK((++it)==tree.end())

	// acid iterator test: BOOST_FOREACH
	int sum = 0;
	BOOST_FOREACH(const KeyInt& p, tree)
sum	+= p.second;
	LONGS_EQUAL(15,sum)

	// STL iterator test
	list<KeyInt> expected, actual;
	expected += p1,p2,p3,p4,p5;
	copy (tree.begin(),tree.end(),back_inserter(actual));
	CHECK(actual==expected)
}

/* ************************************************************************* */
TEST( BTree, remove )
{
	IntTree tree5 = IntTree().add(p1).add(p2).add(p3).add(p4).add(p5);
	LONGS_EQUAL(5,tree5.size())
	CHECK(tree5.mem(x3))
	IntTree tree4 = tree5.remove(x3);
	LONGS_EQUAL(4,tree4.size())
	CHECK(!tree4.mem(x3))
}

/* ************************************************************************* */
TEST( BTree, stress )
{
	RangeTree tree;
	list<RangeTree::value_type> expected;
	int N = 128;
	for (int i = 1; i <= N; i++) {
		string key('a', i);
		Range value(i - 1, i);
		tree = tree.add(key, value);
		LONGS_EQUAL(i,tree.size())
		CHECK(tree.find(key) == value)
		expected += make_pair(key, value);
	}

	// Check height is log(N)
	LONGS_EQUAL(8,tree.height())

	// stress test iterator
	list<RangeTree::value_type> actual;
	copy(tree.begin(), tree.end(), back_inserter(actual));
	CHECK(actual==expected)

	// deconstruct the tree
	for (int i = N; i >= N; i--) {
		string key('a', i);
		tree = tree.remove(key);
		LONGS_EQUAL(i-1,tree.size())
		CHECK(!tree.mem(key))
	}
}

/* ************************************************************************* */
int main() {
	TestResult tr;
	return TestRegistry::runAllTests(tr);
}
/* ************************************************************************* */