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check in two bad ones, start think of column distribut cut row

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tqchen 2014-11-16 13:31:50 -08:00
parent 5061d55725
commit 8ed585a7a2
2 changed files with 88 additions and 3 deletions
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3
src/tree/updater.cpp
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@ -15,7 +15,8 @@ IUpdater* CreateUpdater(const char *name) {
if (!strcmp(name, "prune")) return new TreePruner();
if (!strcmp(name, "refresh")) return new TreeRefresher<GradStats>();
if (!strcmp(name, "grow_colmaker")) return new ColMaker<GradStats>();
if (!strcmp(name, "grow_histmaker")) return new QuantileHistMaker<GradStats>();
if (!strcmp(name, "grow_qhistmaker")) return new QuantileHistMaker<GradStats>();
if (!strcmp(name, "grow_chistmaker")) return new ColumnHistMaker<GradStats>();
if (!strcmp(name, "distcol")) return new DistColMaker<GradStats>();
if (!strcmp(name, "grow_colmaker5")) return new ColMaker< CVGradStats<5> >();
if (!strcmp(name, "grow_colmaker3")) return new ColMaker< CVGradStats<3> >();

88
src/tree/updater_histmaker-inl.hpp
View File

@ -251,7 +251,10 @@ class HistMaker: public IUpdater {
const int tid = omp_get_thread_num();
HistSet &hset = wspace.hset[tid];
const bst_uint ridx = static_cast<bst_uint>(batch.base_rowid + i);
const int nid = position[ridx];
int nid = position[ridx];
if (!tree[nid].is_leaf()) {
this->position[ridx] = nid = HistMaker<TStats>::NextLevel(inst, tree, nid);
}
if (nid >= 0) {
utils::Assert(tree[nid].is_leaf(), "CreateHist happens in leaf");
const int wid = this->node2workindex[nid];
@ -367,7 +370,88 @@ class HistMaker: public IUpdater {
}
};
// hist maker that propose using quantile sketch
template<typename TStats>
class ColumnHistMaker: public HistMaker<TStats> {
public:
virtual void ResetPosAndPropose(const std::vector<bst_gpair> &gpair,
IFMatrix *p_fmat,
const BoosterInfo &info,
const RegTree &tree) {
sketchs.resize(tree.param.num_feature);
for (size_t i = 0; i < sketchs.size(); ++i) {
sketchs[i].Init(info.num_row, this->param.sketch_eps);
}
utils::IIterator<ColBatch> *iter = p_fmat->ColIterator();
while (iter->Next()) {
const ColBatch &batch = iter->Value();
const bst_omp_uint nsize = static_cast<bst_omp_uint>(batch.size);
#pragma omp parallel for schedule(dynamic, 1)
for (bst_omp_uint i = 0; i < nsize; ++i) {
const bst_uint fid = batch.col_index[i];
const ColBatch::Inst &col = batch[i];
unsigned nstep = col.length * (this->param.sketch_eps / this->param.sketch_ratio);
if (nstep == 0) nstep = 1;
for (unsigned i = 0; i < col.length; i += nstep) {
sketchs[fid].Push(col[i].fvalue);
}
if (col.length != 0 && col.length - 1 % nstep != 0) {
sketchs[fid].Push(col[col.length-1].fvalue);
}
}
}
size_t max_size = static_cast<size_t>(this->param.sketch_ratio / this->param.sketch_eps);
// synchronize sketch
summary_array.Init(sketchs.size(), max_size);
for (size_t i = 0; i < sketchs.size(); ++i) {
utils::WQuantileSketch<bst_float, bst_float>::SummaryContainer out;
sketchs[i].GetSummary(&out);
summary_array.Set(i, out);
}
size_t n4bytes = (summary_array.MemSize() + 3) / 4;
sreducer.AllReduce(&summary_array, n4bytes);
// now we get the final result of sketch, setup the cut
this->wspace.cut.clear();
this->wspace.rptr.clear();
this->wspace.rptr.push_back(0);
for (size_t wid = 0; wid < this->qexpand.size(); ++wid) {
for (int fid = 0; fid < tree.param.num_feature; ++fid) {
const WXQSketch::Summary a = summary_array[fid];
for (size_t i = 1; i < a.size; ++i) {
bst_float cpt = a.data[i].value - rt_eps;
if (i == 1 || cpt > this->wspace.cut.back()) {
this->wspace.cut.push_back(cpt);
}
}
// push a value that is greater than anything
if (a.size != 0) {
bst_float cpt = a.data[a.size - 1].value;
// this must be bigger than last value in a scale
bst_float last = cpt + fabs(cpt) + rt_eps;
this->wspace.cut.push_back(last);
}
this->wspace.rptr.push_back(this->wspace.cut.size());
}
// reserve last value for global statistics
this->wspace.cut.push_back(0.0f);
this->wspace.rptr.push_back(this->wspace.cut.size());
}
utils::Assert(this->wspace.rptr.size() ==
(tree.param.num_feature + 1) * this->qexpand.size() + 1,
"cut space inconsistent");
}
private:
typedef utils::WXQuantileSketch<bst_float, bst_float> WXQSketch;
// summary array
WXQSketch::SummaryArray summary_array;
// reducer for summary
sync::ComplexReducer<WXQSketch::SummaryArray> sreducer;
// per feature sketch
std::vector< utils::WQuantileSketch<bst_float, bst_float> > sketchs;
};
template<typename TStats>
class QuantileHistMaker: public HistMaker<TStats> {
protected: