xgboost/tests/cpp/tree/test_refresh.cc
Jiaming Yuan 7d52c0b8c2
Requires setting leaf stat when expanding tree. (#5501)
* Fix GPU Hist feature importance.
2020-04-10 12:27:03 +08:00

58 lines
1.7 KiB
C++

/*!
* Copyright 2018-2019 by Contributors
*/
#include <xgboost/host_device_vector.h>
#include <xgboost/tree_updater.h>
#include <gtest/gtest.h>
#include <vector>
#include <string>
#include <memory>
#include "../helpers.h"
namespace xgboost {
namespace tree {
TEST(Updater, Refresh) {
bst_row_t constexpr kRows = 8;
bst_feature_t constexpr kCols = 16;
HostDeviceVector<GradientPair> gpair =
{ {0.23f, 0.24f}, {0.23f, 0.24f}, {0.23f, 0.24f}, {0.23f, 0.24f},
{0.27f, 0.29f}, {0.27f, 0.29f}, {0.27f, 0.29f}, {0.27f, 0.29f} };
std::shared_ptr<DMatrix> p_dmat{
RandomDataGenerator{kRows, kCols, 0.4f}.Seed(3).GenerateDMatrix()};
std::vector<std::pair<std::string, std::string>> cfg{
{"reg_alpha", "0.0"},
{"num_feature", std::to_string(kCols)},
{"reg_lambda", "1"}};
RegTree tree = RegTree();
auto lparam = CreateEmptyGenericParam(GPUIDX);
tree.param.UpdateAllowUnknown(cfg);
std::vector<RegTree*> trees {&tree};
std::unique_ptr<TreeUpdater> refresher(TreeUpdater::Create("refresh", &lparam));
tree.ExpandNode(0, 2, 0.2f, false, 0.0, 0.2f, 0.8f, 0.0f, 0.0f,
/*left_sum=*/0.0f, /*right_sum=*/0.0f);
int cleft = tree[0].LeftChild();
int cright = tree[0].RightChild();
tree.Stat(cleft).base_weight = 1.2;
tree.Stat(cright).base_weight = 1.3;
refresher->Configure(cfg);
refresher->Update(&gpair, p_dmat.get(), trees);
bst_float constexpr kEps = 1e-6;
ASSERT_NEAR(-0.183392, tree[cright].LeafValue(), kEps);
ASSERT_NEAR(-0.224489, tree.Stat(0).loss_chg, kEps);
ASSERT_NEAR(0, tree.Stat(cleft).loss_chg, kEps);
ASSERT_NEAR(0, tree.Stat(1).loss_chg, kEps);
ASSERT_NEAR(0, tree.Stat(2).loss_chg, kEps);
}
} // namespace tree
} // namespace xgboost