xgboost/python/xgboost_wrapper.cpp
2014-08-17 19:16:17 -07:00

258 lines
9.1 KiB
C++

// implementations in ctypes
#include <cstdio>
#include <vector>
#include <string>
#include <cstring>
#include <algorithm>
#include "./xgboost_wrapper.h"
#include "../src/data.h"
#include "../src/learner/learner-inl.hpp"
#include "../src/io/io.h"
#include "../src/io/simple_dmatrix-inl.hpp"
using namespace xgboost;
using namespace xgboost::io;
namespace xgboost {
namespace wrapper {
// booster wrapper class
class Booster: public learner::BoostLearner<FMatrixS> {
public:
explicit Booster(const std::vector<DataMatrix*>& mats) {
this->silent = 1;
this->init_model = false;
this->SetCacheData(mats);
}
const float *Pred(const DataMatrix &dmat, size_t *len) {
this->CheckInitModel();
this->Predict(dmat, &this->preds_);
*len = this->preds_.size();
return &this->preds_[0];
}
inline void BoostOneIter(const DataMatrix &train,
float *grad, float *hess, size_t len) {
this->gpair_.resize(len);
const unsigned ndata = static_cast<unsigned>(len);
#pragma omp parallel for schedule(static)
for (unsigned j = 0; j < ndata; ++j) {
gpair_[j] = bst_gpair(grad[j], hess[j]);
}
gbm_->DoBoost(gpair_, train.fmat, train.info.root_index);
}
inline void CheckInitModel(void) {
if (!init_model) {
this->InitModel(); init_model = true;
}
}
inline void LoadModel(const char *fname) {
learner::BoostLearner<FMatrixS>::LoadModel(fname);
this->init_model = true;
}
inline const char** GetModelDump(const utils::FeatMap& fmap, bool with_stats, size_t *len) {
model_dump = this->DumpModel(fmap, with_stats);
model_dump_cptr.resize(model_dump.size());
for (size_t i = 0; i < model_dump.size(); ++i) {
model_dump_cptr[i] = model_dump[i].c_str();
}
*len = model_dump.size();
return &model_dump_cptr[0];
}
// temporal fields
// temporal data to save evaluation dump
std::string eval_str;
// temporal space to save model dump
std::vector<std::string> model_dump;
std::vector<const char*> model_dump_cptr;
private:
bool init_model;
};
} // namespace wrapper
} // namespace xgboost
using namespace xgboost::wrapper;
extern "C"{
void* XGDMatrixCreateFromFile(const char *fname, int silent) {
return LoadDataMatrix(fname, silent, false);
}
void* XGDMatrixCreateFromCSR(const size_t *indptr,
const unsigned *indices,
const float *data,
size_t nindptr,
size_t nelem) {
DMatrixSimple *p_mat = new DMatrixSimple();
DMatrixSimple &mat = *p_mat;
mat.row_ptr_.resize(nindptr);
memcpy(&mat.row_ptr_[0], indptr, sizeof(size_t)*nindptr);
mat.row_data_.resize(nelem);
for (size_t i = 0; i < nelem; ++i) {
mat.row_data_[i] = SparseBatch::Entry(indices[i], data[i]);
mat.info.num_col = std::max(mat.info.num_col,
static_cast<size_t>(indices[i]+1));
}
mat.info.num_row = nindptr - 1;
return p_mat;
}
void* XGDMatrixCreateFromMat(const float *data,
size_t nrow,
size_t ncol,
float missing) {
DMatrixSimple *p_mat = new DMatrixSimple();
DMatrixSimple &mat = *p_mat;
mat.info.num_row = nrow;
mat.info.num_col = ncol;
for (size_t i = 0; i < nrow; ++i, data += ncol) {
size_t nelem = 0;
for (size_t j = 0; j < ncol; ++j) {
if (data[j] != missing) {
mat.row_data_.push_back(SparseBatch::Entry(j, data[j]));
++nelem;
}
}
mat.row_ptr_.push_back(mat.row_ptr_.back() + nelem);
}
return p_mat;
}
void* XGDMatrixSliceDMatrix(void *handle,
const int *idxset,
size_t len) {
DMatrixSimple tmp;
DataMatrix &dsrc = *static_cast<DataMatrix*>(handle);
if (dsrc.magic != DMatrixSimple::kMagic) {
tmp.CopyFrom(dsrc);
}
DataMatrix &src = (dsrc.magic == DMatrixSimple::kMagic ?
*static_cast<DMatrixSimple*>(handle): tmp);
DMatrixSimple *p_ret = new DMatrixSimple();
DMatrixSimple &ret = *p_ret;
utils::Check(src.info.group_ptr.size() == 0,
"slice does not support group structure");
ret.Clear();
ret.info.num_row = len;
ret.info.num_col = src.info.num_col;
utils::IIterator<SparseBatch> *iter = src.fmat.RowIterator();
iter->BeforeFirst();
utils::Assert(iter->Next(), "slice");
const SparseBatch &batch = iter->Value();
for (size_t i = 0; i < len; ++i) {
const int ridx = idxset[i];
SparseBatch::Inst inst = batch[ridx];
utils::Check(ridx < batch.size, "slice index exceed number of rows");
ret.row_data_.resize(ret.row_data_.size() + inst.length);
memcpy(&ret.row_data_[ret.row_ptr_.back()], inst.data,
sizeof(SparseBatch::Entry) * inst.length);
ret.row_ptr_.push_back(ret.row_ptr_.back() + inst.length);
if (src.info.labels.size() != 0) {
ret.info.labels.push_back(src.info.labels[ridx]);
}
if (src.info.weights.size() != 0) {
ret.info.weights.push_back(src.info.weights[ridx]);
}
if (src.info.root_index.size() != 0) {
ret.info.weights.push_back(src.info.root_index[ridx]);
}
}
return p_ret;
}
void XGDMatrixFree(void *handle) {
delete static_cast<DataMatrix*>(handle);
}
void XGDMatrixSaveBinary(void *handle, const char *fname, int silent) {
SaveDataMatrix(*static_cast<DataMatrix*>(handle), fname, silent);
}
void XGDMatrixSetLabel(void *handle, const float *label, size_t len) {
DataMatrix *pmat = static_cast<DataMatrix*>(handle);
pmat->info.labels.resize(len);
memcpy(&(pmat->info).labels[0], label, sizeof(float) * len);
}
void XGDMatrixSetWeight(void *handle, const float *weight, size_t len) {
DataMatrix *pmat = static_cast<DataMatrix*>(handle);
pmat->info.weights.resize(len);
memcpy(&(pmat->info).weights[0], weight, sizeof(float) * len);
}
void XGDMatrixSetGroup(void *handle, const unsigned *group, size_t len) {
DataMatrix *pmat = static_cast<DataMatrix*>(handle);
pmat->info.group_ptr.resize(len + 1);
pmat->info.group_ptr[0] = 0;
for (size_t i = 0; i < len; ++i) {
pmat->info.group_ptr[i+1] = pmat->info.group_ptr[i]+group[i];
}
}
const float* XGDMatrixGetLabel(const void *handle, size_t* len) {
const DataMatrix *pmat = static_cast<const DataMatrix*>(handle);
*len = pmat->info.labels.size();
return &(pmat->info.labels[0]);
}
const float* XGDMatrixGetWeight(const void *handle, size_t* len) {
const DataMatrix *pmat = static_cast<const DataMatrix*>(handle);
*len = pmat->info.weights.size();
return &(pmat->info.weights[0]);
}
size_t XGDMatrixNumRow(const void *handle) {
return static_cast<const DataMatrix*>(handle)->info.num_row;
}
// xgboost implementation
void *XGBoosterCreate(void *dmats[], size_t len) {
std::vector<DataMatrix*> mats;
for (size_t i = 0; i < len; ++i) {
DataMatrix *dtr = static_cast<DataMatrix*>(dmats[i]);
mats.push_back(dtr);
}
return new Booster(mats);
}
void XGBoosterFree(void *handle) {
delete static_cast<Booster*>(handle);
}
void XGBoosterSetParam(void *handle, const char *name, const char *value) {
static_cast<Booster*>(handle)->SetParam(name, value);
}
void XGBoosterUpdateOneIter(void *handle, int iter, void *dtrain) {
Booster *bst = static_cast<Booster*>(handle);
DataMatrix *dtr = static_cast<DataMatrix*>(dtrain);
bst->CheckInitModel();
bst->CheckInit(dtr);
bst->UpdateOneIter(iter, *dtr);
}
void XGBoosterBoostOneIter(void *handle, void *dtrain,
float *grad, float *hess, size_t len) {
Booster *bst = static_cast<Booster*>(handle);
DataMatrix *dtr = static_cast<DataMatrix*>(dtrain);
bst->CheckInitModel();
bst->CheckInit(dtr);
bst->BoostOneIter(*dtr, grad, hess, len);
}
const char* XGBoosterEvalOneIter(void *handle, int iter, void *dmats[],
const char *evnames[], size_t len) {
Booster *bst = static_cast<Booster*>(handle);
std::vector<std::string> names;
std::vector<const DataMatrix*> mats;
for (size_t i = 0; i < len; ++i) {
mats.push_back(static_cast<DataMatrix*>(dmats[i]));
names.push_back(std::string(evnames[i]));
}
bst->CheckInitModel();
bst->eval_str = bst->EvalOneIter(iter, mats, names);
return bst->eval_str.c_str();
}
const float *XGBoosterPredict(void *handle, void *dmat, size_t *len) {
return static_cast<Booster*>(handle)->Pred(*static_cast<DataMatrix*>(dmat), len);
}
void XGBoosterLoadModel(void *handle, const char *fname) {
static_cast<Booster*>(handle)->LoadModel(fname);
}
void XGBoosterSaveModel(const void *handle, const char *fname) {
static_cast<const Booster*>(handle)->SaveModel(fname);
}
const char** XGBoosterDumpModel(void *handle, const char *fmap, size_t *len){
utils::FeatMap featmap;
if (strlen(fmap) != 0) {
featmap.LoadText(fmap);
}
return static_cast<Booster*>(handle)->GetModelDump(featmap, false, len);
}
};