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simplify

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This commit is contained in:
tqchen 2014-11-18 10:52:18 -08:00
parent 5de0a2cdc0
commit ce7ecadf5e
1 changed files with 22 additions and 28 deletions
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50
src/tree/updater_histmaker-inl.hpp
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@ -377,8 +377,7 @@ class CQHistMaker: public HistMaker<TStats> {
for (size_t i = 0; i < sketchs.size(); ++i) {
sketchs[i].Init(info.num_row, this->param.sketch_eps);
}
std::vector< std::vector<SketchEntry> > stemp;
stemp.resize(this->get_nthread());
thread_temp.resize(this->get_nthread());
// start accumulating statistics
utils::IIterator<ColBatch> *iter = p_fmat->ColIterator();
@ -390,7 +389,7 @@ class CQHistMaker: public HistMaker<TStats> {
#pragma omp parallel for schedule(dynamic, 1)
for (bst_omp_uint i = 0; i < nsize; ++i) {
this->MakeSketch(gpair, batch[i], tree, batch.col_index[i],
&stemp[omp_get_thread_num()]);
&thread_temp[omp_get_thread_num()]);
}
}
// setup maximum size
@ -460,7 +459,6 @@ class CQHistMaker: public HistMaker<TStats> {
* \param max_size
*/
inline void Push(bst_float fvalue, bst_float w, unsigned max_size) {
if (w == 0.0f) return;
if (wmin == 0.0f) {
last_fvalue = fvalue;
wmin = w;
@ -520,56 +518,52 @@ class CQHistMaker: public HistMaker<TStats> {
if (c.length == 0) return;
// initialize sbuilder for use
std::vector<SketchEntry> &sbuilder = *p_temp;
sbuilder.resize(this->qexpand.size());
for (size_t i = 0; i < sbuilder.size(); ++i) {
sbuilder[i].sum_total = 0.0f;
sbuilder[i].sketch = &sketchs[i * tree.param.num_feature + fid];
sbuilder.resize(tree.param.num_nodes);
for (size_t i = 0; i < this->qexpand.size(); ++i) {
const unsigned nid = this->qexpand[i];
const unsigned wid = this->node2workindex[nid];
sbuilder[nid].sum_total = 0.0f;
sbuilder[nid].sketch = &sketchs[wid * tree.param.num_feature + fid];
}
// second pass, build the sketch
for (bst_uint j = 0; j < c.length; ++j) {
const bst_uint ridx = c[j].index;
const int nid = this->position[ridx];
if (nid >= 0) {
const int wid = this->node2workindex[nid];
sbuilder[wid].sketch->Push(c[j].fvalue, gpair[ridx].hess);
}
}
return;
// first pass, get sum of weight, TODO, optimization to skip first pass
for (bst_uint j = 0; j < c.length; ++j) {
const bst_uint ridx = c[j].index;
const int nid = this->position[ridx];
if (nid >= 0) {
const int wid = this->node2workindex[nid];
sbuilder[wid].sum_total += gpair[ridx].hess;
sbuilder[nid].sum_total += gpair[ridx].hess;
}
}
// if only one value, no need to do second pass
if (c[0].fvalue == c[c.length-1].fvalue) {
for (size_t wid = 0; wid < this->qexpand.size(); ++wid) {
sbuilder[wid].sketch->Push(c[0].fvalue, sbuilder[wid].sum_total);
for (size_t i = 0; i < this->qexpand.size(); ++i) {
const int nid = this->qexpand[i];
sbuilder[nid].sketch->Push(c[0].fvalue, sbuilder[nid].sum_total);
}
return;
}
// two pass scan
unsigned max_size = static_cast<unsigned>(this->param.sketch_ratio / this->param.sketch_eps);
for (size_t wid = 0; wid < sbuilder.size(); ++wid) {
sbuilder[wid].Init(max_size);
for (size_t i = 0; i < this->qexpand.size(); ++i) {
const int nid = this->qexpand[i];
sbuilder[nid].Init(max_size);
}
// second pass, build the sketch
for (bst_uint j = 0; j < c.length; ++j) {
const bst_uint ridx = c[j].index;
const int nid = this->position[ridx];
if (nid >= 0) {
const int wid = this->node2workindex[nid];
sbuilder[wid].Push(c[j].fvalue, gpair[ridx].hess, max_size);
sbuilder[nid].Push(c[j].fvalue, gpair[ridx].hess, max_size);
}
}
for (size_t wid = 0; wid < sbuilder.size(); ++wid) {
sbuilder[wid].Finalize(max_size);
for (size_t i = 0; i < this->qexpand.size(); ++i) {
const int nid = this->qexpand[i];
sbuilder[nid].Finalize(max_size);
}
}
typedef utils::WXQuantileSketch<bst_float, bst_float> WXQSketch;
// thread temp data
std::vector< std::vector<SketchEntry> > thread_temp;
// summary array
WXQSketch::SummaryArray summary_array;
// reducer for summary