--- /dev/null
+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+// By downloading, copying, installing or using the software you agree to this license.
+// If you do not agree to this license, do not download, install,
+// copy or use the software.
+//
+//
+// Intel License Agreement
+//
+// Copyright (C) 2000, Intel Corporation, all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+// * Redistribution's of source code must retain the above copyright notice,
+// this list of conditions and the following disclaimer.
+//
+// * Redistribution's in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution.
+//
+// * The name of Intel Corporation may not be used to endorse or promote products
+// derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "_ml.h"
+
+CvForestTree::CvForestTree()
+{
+ forest = NULL;
+}
+
+
+CvForestTree::~CvForestTree()
+{
+ clear();
+}
+
+
+bool CvForestTree::train( CvDTreeTrainData* _data,
+ const CvMat* _subsample_idx,
+ CvRTrees* _forest )
+{
+ clear();
+ forest = _forest;
+
+ data = _data;
+ data->shared = true;
+ return do_train(_subsample_idx);
+}
+
+
+bool
+CvForestTree::train( const CvMat*, int, const CvMat*, const CvMat*,
+ const CvMat*, const CvMat*, const CvMat*, CvDTreeParams )
+{
+ assert(0);
+ return false;
+}
+
+
+bool
+CvForestTree::train( CvDTreeTrainData*, const CvMat* )
+{
+ assert(0);
+ return false;
+}
+
+
+CvDTreeSplit* CvForestTree::find_best_split( CvDTreeNode* node )
+{
+ int vi;
+
+ CvDTreeSplit *best_split = 0;
+
+ CvMat* active_var_mask = 0;
+ if( forest )
+ {
+ int var_count;
+ CvRNG* rng = forest->get_rng();
+
+ active_var_mask = forest->get_active_var_mask();
+ var_count = active_var_mask->cols;
+
+ CV_Assert( var_count == data->var_count );
+
+ for( vi = 0; vi < var_count; vi++ )
+ {
+ uchar temp;
+ int i1 = cvRandInt(rng) % var_count;
+ int i2 = cvRandInt(rng) % var_count;
+ CV_SWAP( active_var_mask->data.ptr[i1],
+ active_var_mask->data.ptr[i2], temp );
+ }
+ }
+ int maxNumThreads = 1;
+#ifdef _OPENMP
+ maxNumThreads = cv::getNumThreads();
+#endif
+ vector<CvDTreeSplit*> splits(maxNumThreads);
+ vector<CvDTreeSplit*> bestSplits(maxNumThreads);
+ vector<int> canSplit(maxNumThreads);
+ CvDTreeSplit **splitsPtr = &splits[0], ** bestSplitsPtr = &bestSplits[0];
+ int* canSplitPtr = &canSplit[0];
+ for (int i = 0; i < maxNumThreads; i++)
+ {
+ splits[i] = data->new_split_cat( 0, -1.0f );
+ bestSplits[i] = data->new_split_cat( 0, -1.0f );
+ canSplitPtr[i] = 0;
+ }
+
+#ifdef _OPENMP
+#pragma omp parallel for num_threads(maxNumThreads) schedule(dynamic)
+#endif
+ for( vi = 0; vi < data->var_count; vi++ )
+ {
+ CvDTreeSplit *res, *t;
+ int threadIdx = cv::getThreadNum();
+ int ci = data->var_type->data.i[vi];
+ if( node->num_valid[vi] <= 1
+ || (active_var_mask && !active_var_mask->data.ptr[vi]) )
+ continue;
+
+ if( data->is_classifier )
+ {
+ if( ci >= 0 )
+ res = find_split_cat_class( node, vi, bestSplitsPtr[threadIdx]->quality, splitsPtr[threadIdx] );
+ else
+ res = find_split_ord_class( node, vi, bestSplitsPtr[threadIdx]->quality, splitsPtr[threadIdx] );
+ }
+ else
+ {
+ if( ci >= 0 )
+ res = find_split_cat_reg( node, vi, bestSplitsPtr[threadIdx]->quality, splitsPtr[threadIdx] );
+ else
+ res = find_split_ord_reg( node, vi, bestSplitsPtr[threadIdx]->quality, splitsPtr[threadIdx] );
+ }
+
+ if( res )
+ {
+ canSplitPtr[threadIdx] = 1;
+ if( bestSplits[threadIdx]->quality < splits[threadIdx]->quality )
+ CV_SWAP( bestSplits[threadIdx], splits[threadIdx], t );
+ }
+ }
+ int ti = 0;
+ for( ; ti < maxNumThreads; ti++ )
+ {
+ if( canSplitPtr[ti] )
+ {
+ best_split = bestSplitsPtr[ti];
+ break;
+ }
+ }
+ for( ; ti < maxNumThreads; ti++ )
+ {
+ if( best_split->quality < bestSplitsPtr[ti]->quality )
+ best_split = bestSplitsPtr[ti];
+ }
+ for(int i = 0; i < maxNumThreads; i++)
+ {
+ cvSetRemoveByPtr( data->split_heap, splits[i] );
+ if( bestSplits[i] != best_split )
+ cvSetRemoveByPtr( data->split_heap, bestSplits[i] );
+ }
+ return best_split;
+}
+
+
+void CvForestTree::read( CvFileStorage* fs, CvFileNode* fnode, CvRTrees* _forest, CvDTreeTrainData* _data )
+{
+ CvDTree::read( fs, fnode, _data );
+ forest = _forest;
+}
+
+
+void CvForestTree::read( CvFileStorage*, CvFileNode* )
+{
+ assert(0);
+}
+
+void CvForestTree::read( CvFileStorage* _fs, CvFileNode* _node,
+ CvDTreeTrainData* _data )
+{
+ CvDTree::read( _fs, _node, _data );
+}
+
+
+//////////////////////////////////////////////////////////////////////////////////////////
+// Random trees //
+//////////////////////////////////////////////////////////////////////////////////////////
+
+CvRTrees::CvRTrees()
+{
+ nclasses = 0;
+ oob_error = 0;
+ ntrees = 0;
+ trees = NULL;
+ data = NULL;
+ active_var_mask = NULL;
+ var_importance = NULL;
+ rng = cvRNG(0xffffffff);
+ default_model_name = "my_random_trees";
+}
+
+
+void CvRTrees::clear()
+{
+ int k;
+ for( k = 0; k < ntrees; k++ )
+ delete trees[k];
+ cvFree( &trees );
+
+ delete data;
+ data = 0;
+
+ cvReleaseMat( &active_var_mask );
+ cvReleaseMat( &var_importance );
+ ntrees = 0;
+}
+
+
+CvRTrees::~CvRTrees()
+{
+ clear();
+}
+
+
+CvMat* CvRTrees::get_active_var_mask()
+{
+ return active_var_mask;
+}
+
+
+CvRNG* CvRTrees::get_rng()
+{
+ return &rng;
+}
+
+bool CvRTrees::train( const CvMat* _train_data, int _tflag,
+ const CvMat* _responses, const CvMat* _var_idx,
+ const CvMat* _sample_idx, const CvMat* _var_type,
+ const CvMat* _missing_mask, CvRTParams params )
+{
+ clear();
+
+ CvDTreeParams tree_params( params.max_depth, params.min_sample_count,
+ params.regression_accuracy, params.use_surrogates, params.max_categories,
+ params.cv_folds, params.use_1se_rule, false, params.priors );
+
+ data = new CvDTreeTrainData();
+ data->set_data( _train_data, _tflag, _responses, _var_idx,
+ _sample_idx, _var_type, _missing_mask, tree_params, true);
+
+ int var_count = data->var_count;
+ if( params.nactive_vars > var_count )
+ params.nactive_vars = var_count;
+ else if( params.nactive_vars == 0 )
+ params.nactive_vars = (int)sqrt((double)var_count);
+ else if( params.nactive_vars < 0 )
+ CV_Error( CV_StsBadArg, "<nactive_vars> must be non-negative" );
+
+ // Create mask of active variables at the tree nodes
+ active_var_mask = cvCreateMat( 1, var_count, CV_8UC1 );
+ if( params.calc_var_importance )
+ {
+ var_importance = cvCreateMat( 1, var_count, CV_32FC1 );
+ cvZero(var_importance);
+ }
+ { // initialize active variables mask
+ CvMat submask1, submask2;
+ cvGetCols( active_var_mask, &submask1, 0, params.nactive_vars );
+ cvGetCols( active_var_mask, &submask2, params.nactive_vars, var_count );
+ cvSet( &submask1, cvScalar(1) );
+ cvZero( &submask2 );
+ }
+
+ return grow_forest( params.term_crit );
+}
+
+bool CvRTrees::train( CvMLData* data, CvRTParams params )
+{
+ const CvMat* values = data->get_values();
+ const CvMat* response = data->get_responses();
+ const CvMat* missing = data->get_missing();
+ const CvMat* var_types = data->get_var_types();
+ const CvMat* train_sidx = data->get_train_sample_idx();
+ const CvMat* var_idx = data->get_var_idx();
+
+ return train( values, CV_ROW_SAMPLE, response, var_idx,
+ train_sidx, var_types, missing, params );
+}
+
+bool CvRTrees::grow_forest( const CvTermCriteria term_crit )
+{
+ CvMat* sample_idx_mask_for_tree = 0;
+ CvMat* sample_idx_for_tree = 0;
+
+ const int max_ntrees = term_crit.max_iter;
+ const double max_oob_err = term_crit.epsilon;
+
+ const int dims = data->var_count;
+ float maximal_response = 0;
+
+ CvMat* oob_sample_votes = 0;
+ CvMat* oob_responses = 0;
+
+ float* oob_samples_perm_ptr= 0;
+
+ float* samples_ptr = 0;
+ uchar* missing_ptr = 0;
+ float* true_resp_ptr = 0;
+ bool is_oob_or_vimportance = (max_oob_err > 0) && (term_crit.type != CV_TERMCRIT_ITER) || var_importance;
+
+ // oob_predictions_sum[i] = sum of predicted values for the i-th sample
+ // oob_num_of_predictions[i] = number of summands
+ // (number of predictions for the i-th sample)
+ // initialize these variable to avoid warning C4701
+ CvMat oob_predictions_sum = cvMat( 1, 1, CV_32FC1 );
+ CvMat oob_num_of_predictions = cvMat( 1, 1, CV_32FC1 );
+
+ nsamples = data->sample_count;
+ nclasses = data->get_num_classes();
+
+ if ( is_oob_or_vimportance )
+ {
+ if( data->is_classifier )
+ {
+ oob_sample_votes = cvCreateMat( nsamples, nclasses, CV_32SC1 );
+ cvZero(oob_sample_votes);
+ }
+ else
+ {
+ // oob_responses[0,i] = oob_predictions_sum[i]
+ // = sum of predicted values for the i-th sample
+ // oob_responses[1,i] = oob_num_of_predictions[i]
+ // = number of summands (number of predictions for the i-th sample)
+ oob_responses = cvCreateMat( 2, nsamples, CV_32FC1 );
+ cvZero(oob_responses);
+ cvGetRow( oob_responses, &oob_predictions_sum, 0 );
+ cvGetRow( oob_responses, &oob_num_of_predictions, 1 );
+ }
+
+ oob_samples_perm_ptr = (float*)cvAlloc( sizeof(float)*nsamples*dims );
+ samples_ptr = (float*)cvAlloc( sizeof(float)*nsamples*dims );
+ missing_ptr = (uchar*)cvAlloc( sizeof(uchar)*nsamples*dims );
+ true_resp_ptr = (float*)cvAlloc( sizeof(float)*nsamples );
+
+ data->get_vectors( 0, samples_ptr, missing_ptr, true_resp_ptr );
+
+ double minval, maxval;
+ CvMat responses = cvMat(1, nsamples, CV_32FC1, true_resp_ptr);
+ cvMinMaxLoc( &responses, &minval, &maxval );
+ maximal_response = (float)MAX( MAX( fabs(minval), fabs(maxval) ), 0 );
+ }
+
+ trees = (CvForestTree**)cvAlloc( sizeof(trees[0])*max_ntrees );
+ memset( trees, 0, sizeof(trees[0])*max_ntrees );
+
+ sample_idx_mask_for_tree = cvCreateMat( 1, nsamples, CV_8UC1 );
+ sample_idx_for_tree = cvCreateMat( 1, nsamples, CV_32SC1 );
+
+ ntrees = 0;
+ while( ntrees < max_ntrees )
+ {
+ int i, oob_samples_count = 0;
+ double ncorrect_responses = 0; // used for estimation of variable importance
+ CvForestTree* tree = 0;
+
+ cvZero( sample_idx_mask_for_tree );
+ for(i = 0; i < nsamples; i++ ) //form sample for creation one tree
+ {
+ int idx = cvRandInt( &rng ) % nsamples;
+ sample_idx_for_tree->data.i[i] = idx;
+ sample_idx_mask_for_tree->data.ptr[idx] = 0xFF;
+ }
+
+ trees[ntrees] = new CvForestTree();
+ tree = trees[ntrees];
+ tree->train( data, sample_idx_for_tree, this );
+
+ if ( is_oob_or_vimportance )
+ {
+ CvMat sample, missing;
+ // form array of OOB samples indices and get these samples
+ sample = cvMat( 1, dims, CV_32FC1, samples_ptr );
+ missing = cvMat( 1, dims, CV_8UC1, missing_ptr );
+
+ oob_error = 0;
+ for( i = 0; i < nsamples; i++,
+ sample.data.fl += dims, missing.data.ptr += dims )
+ {
+ CvDTreeNode* predicted_node = 0;
+ // check if the sample is OOB
+ if( sample_idx_mask_for_tree->data.ptr[i] )
+ continue;
+
+ // predict oob samples
+ if( !predicted_node )
+ predicted_node = tree->predict(&sample, &missing, true);
+
+ if( !data->is_classifier ) //regression
+ {
+ double avg_resp, resp = predicted_node->value;
+ oob_predictions_sum.data.fl[i] += (float)resp;
+ oob_num_of_predictions.data.fl[i] += 1;
+
+ // compute oob error
+ avg_resp = oob_predictions_sum.data.fl[i]/oob_num_of_predictions.data.fl[i];
+ avg_resp -= true_resp_ptr[i];
+ oob_error += avg_resp*avg_resp;
+ resp = (resp - true_resp_ptr[i])/maximal_response;
+ ncorrect_responses += exp( -resp*resp );
+ }
+ else //classification
+ {
+ double prdct_resp;
+ CvPoint max_loc;
+ CvMat votes;
+
+ cvGetRow(oob_sample_votes, &votes, i);
+ votes.data.i[predicted_node->class_idx]++;
+
+ // compute oob error
+ cvMinMaxLoc( &votes, 0, 0, 0, &max_loc );
+
+ prdct_resp = data->cat_map->data.i[max_loc.x];
+ oob_error += (fabs(prdct_resp - true_resp_ptr[i]) < FLT_EPSILON) ? 0 : 1;
+
+ ncorrect_responses += cvRound(predicted_node->value - true_resp_ptr[i]) == 0;
+ }
+ oob_samples_count++;
+ }
+ if( oob_samples_count > 0 )
+ oob_error /= (double)oob_samples_count;
+
+ // estimate variable importance
+ if( var_importance && oob_samples_count > 0 )
+ {
+ int m;
+
+ memcpy( oob_samples_perm_ptr, samples_ptr, dims*nsamples*sizeof(float));
+ for( m = 0; m < dims; m++ )
+ {
+ double ncorrect_responses_permuted = 0;
+ // randomly permute values of the m-th variable in the oob samples
+ float* mth_var_ptr = oob_samples_perm_ptr + m;
+
+ for( i = 0; i < nsamples; i++ )
+ {
+ int i1, i2;
+ float temp;
+
+ if( sample_idx_mask_for_tree->data.ptr[i] ) //the sample is not OOB
+ continue;
+ i1 = cvRandInt( &rng ) % nsamples;
+ i2 = cvRandInt( &rng ) % nsamples;
+ CV_SWAP( mth_var_ptr[i1*dims], mth_var_ptr[i2*dims], temp );
+
+ // turn values of (m-1)-th variable, that were permuted
+ // at the previous iteration, untouched
+ if( m > 1 )
+ oob_samples_perm_ptr[i*dims+m-1] = samples_ptr[i*dims+m-1];
+ }
+
+ // predict "permuted" cases and calculate the number of votes for the
+ // correct class in the variable-m-permuted oob data
+ sample = cvMat( 1, dims, CV_32FC1, oob_samples_perm_ptr );
+ missing = cvMat( 1, dims, CV_8UC1, missing_ptr );
+ for( i = 0; i < nsamples; i++,
+ sample.data.fl += dims, missing.data.ptr += dims )
+ {
+ double predct_resp, true_resp;
+
+ if( sample_idx_mask_for_tree->data.ptr[i] ) //the sample is not OOB
+ continue;
+
+ predct_resp = tree->predict(&sample, &missing, true)->value;
+ true_resp = true_resp_ptr[i];
+ if( data->is_classifier )
+ ncorrect_responses_permuted += cvRound(true_resp - predct_resp) == 0;
+ else
+ {
+ true_resp = (true_resp - predct_resp)/maximal_response;
+ ncorrect_responses_permuted += exp( -true_resp*true_resp );
+ }
+ }
+ var_importance->data.fl[m] += (float)(ncorrect_responses
+ - ncorrect_responses_permuted);
+ }
+ }
+ }
+ ntrees++;
+ if( term_crit.type != CV_TERMCRIT_ITER && oob_error < max_oob_err )
+ break;
+ }
+
+ if( var_importance )
+ {
+ for ( int vi = 0; vi < var_importance->cols; vi++ )
+ var_importance->data.fl[vi] = ( var_importance->data.fl[vi] > 0 ) ?
+ var_importance->data.fl[vi] : 0;
+ cvNormalize( var_importance, var_importance, 1., 0, CV_L1 );
+ }
+
+ cvFree( &oob_samples_perm_ptr );
+ cvFree( &samples_ptr );
+ cvFree( &missing_ptr );
+ cvFree( &true_resp_ptr );
+
+ cvReleaseMat( &sample_idx_mask_for_tree );
+ cvReleaseMat( &sample_idx_for_tree );
+
+ cvReleaseMat( &oob_sample_votes );
+ cvReleaseMat( &oob_responses );
+
+ return true;
+}
+
+
+const CvMat* CvRTrees::get_var_importance()
+{
+ return var_importance;
+}
+
+
+float CvRTrees::get_proximity( const CvMat* sample1, const CvMat* sample2,
+ const CvMat* missing1, const CvMat* missing2 ) const
+{
+ float result = 0;
+
+ for( int i = 0; i < ntrees; i++ )
+ result += trees[i]->predict( sample1, missing1 ) ==
+ trees[i]->predict( sample2, missing2 ) ? 1 : 0;
+ result = result/(float)ntrees;
+
+ return result;
+}
+
+float CvRTrees::calc_error( CvMLData* _data, int type , vector<float> *resp )
+{
+ float err = 0;
+ const CvMat* values = _data->get_values();
+ const CvMat* response = _data->get_responses();
+ const CvMat* missing = _data->get_missing();
+ const CvMat* sample_idx = (type == CV_TEST_ERROR) ? _data->get_test_sample_idx() : _data->get_train_sample_idx();
+ const CvMat* var_types = _data->get_var_types();
+ int* sidx = sample_idx ? sample_idx->data.i : 0;
+ int r_step = CV_IS_MAT_CONT(response->type) ?
+ 1 : response->step / CV_ELEM_SIZE(response->type);
+ bool is_classifier = var_types->data.ptr[var_types->cols-1] == CV_VAR_CATEGORICAL;
+ int sample_count = sample_idx ? sample_idx->cols : 0;
+ sample_count = (type == CV_TRAIN_ERROR && sample_count == 0) ? values->rows : sample_count;
+ float* pred_resp = 0;
+ if( resp && (sample_count > 0) )
+ {
+ resp->resize( sample_count );
+ pred_resp = &((*resp)[0]);
+ }
+ if ( is_classifier )
+ {
+ for( int i = 0; i < sample_count; i++ )
+ {
+ CvMat sample, miss;
+ int si = sidx ? sidx[i] : i;
+ cvGetRow( values, &sample, si );
+ if( missing )
+ cvGetRow( missing, &miss, si );
+ float r = (float)predict( &sample, missing ? &miss : 0 );
+ if( pred_resp )
+ pred_resp[i] = r;
+ int d = fabs((double)r - response->data.fl[si*r_step]) <= FLT_EPSILON ? 0 : 1;
+ err += d;
+ }
+ err = sample_count ? err / (float)sample_count * 100 : -FLT_MAX;
+ }
+ else
+ {
+ for( int i = 0; i < sample_count; i++ )
+ {
+ CvMat sample, miss;
+ int si = sidx ? sidx[i] : i;
+ cvGetRow( values, &sample, si );
+ if( missing )
+ cvGetRow( missing, &miss, si );
+ float r = (float)predict( &sample, missing ? &miss : 0 );
+ if( pred_resp )
+ pred_resp[i] = r;
+ float d = r - response->data.fl[si*r_step];
+ err += d*d;
+ }
+ err = sample_count ? err / (float)sample_count : -FLT_MAX;
+ }
+ return err;
+}
+
+float CvRTrees::get_train_error()
+{
+ float err = -1;
+
+ int sample_count = data->sample_count;
+ int var_count = data->var_count;
+
+ float *values_ptr = (float*)cvAlloc( sizeof(float)*sample_count*var_count );
+ uchar *missing_ptr = (uchar*)cvAlloc( sizeof(uchar)*sample_count*var_count );
+ float *responses_ptr = (float*)cvAlloc( sizeof(float)*sample_count );
+
+ data->get_vectors( 0, values_ptr, missing_ptr, responses_ptr);
+
+ if (data->is_classifier)
+ {
+ int err_count = 0;
+ float *vp = values_ptr;
+ uchar *mp = missing_ptr;
+ for (int si = 0; si < sample_count; si++, vp += var_count, mp += var_count)
+ {
+ CvMat sample = cvMat( 1, var_count, CV_32FC1, vp );
+ CvMat missing = cvMat( 1, var_count, CV_8UC1, mp );
+ float r = predict( &sample, &missing );
+ if (fabs(r - responses_ptr[si]) >= FLT_EPSILON)
+ err_count++;
+ }
+ err = (float)err_count / (float)sample_count;
+ }
+ else
+ CV_Error( CV_StsBadArg, "This method is not supported for regression problems" );
+
+ cvFree( &values_ptr );
+ cvFree( &missing_ptr );
+ cvFree( &responses_ptr );
+
+ return err;
+}
+
+
+float CvRTrees::predict( const CvMat* sample, const CvMat* missing ) const
+{
+ double result = -1;
+ int k;
+
+ if( nclasses > 0 ) //classification
+ {
+ int max_nvotes = 0;
+ int* votes = (int*)alloca( sizeof(int)*nclasses );
+ memset( votes, 0, sizeof(*votes)*nclasses );
+ for( k = 0; k < ntrees; k++ )
+ {
+ CvDTreeNode* predicted_node = trees[k]->predict( sample, missing );
+ int nvotes;
+ int class_idx = predicted_node->class_idx;
+ CV_Assert( 0 <= class_idx && class_idx < nclasses );
+
+ nvotes = ++votes[class_idx];
+ if( nvotes > max_nvotes )
+ {
+ max_nvotes = nvotes;
+ result = predicted_node->value;
+ }
+ }
+ }
+ else // regression
+ {
+ result = 0;
+ for( k = 0; k < ntrees; k++ )
+ result += trees[k]->predict( sample, missing )->value;
+ result /= (double)ntrees;
+ }
+
+ return (float)result;
+}
+
+float CvRTrees::predict_prob( const CvMat* sample, const CvMat* missing) const
+{
+ double result = -1;
+ int k;
+
+ if( nclasses == 2 ) //classification
+ {
+ int max_nvotes = 0;
+ int* votes = (int*)alloca( sizeof(int)*nclasses );
+ memset( votes, 0, sizeof(*votes)*nclasses );
+ for( k = 0; k < ntrees; k++ )
+ {
+ CvDTreeNode* predicted_node = trees[k]->predict( sample, missing );
+ int nvotes;
+ int class_idx = predicted_node->class_idx;
+ CV_Assert( 0 <= class_idx && class_idx < nclasses );
+
+ nvotes = ++votes[class_idx];
+ if( nvotes > max_nvotes )
+ {
+ max_nvotes = nvotes;
+ result = predicted_node->value;
+ }
+ }
+
+ return float(votes[1])/ntrees;
+ }
+ else // regression
+ CV_Error(CV_StsBadArg, "This function works for binary classification problems only...");
+
+ return -1;
+}
+
+void CvRTrees::write( CvFileStorage* fs, const char* name ) const
+{
+ int k;
+
+ if( ntrees < 1 || !trees || nsamples < 1 )
+ CV_Error( CV_StsBadArg, "Invalid CvRTrees object" );
+
+ cvStartWriteStruct( fs, name, CV_NODE_MAP, CV_TYPE_NAME_ML_RTREES );
+
+ cvWriteInt( fs, "nclasses", nclasses );
+ cvWriteInt( fs, "nsamples", nsamples );
+ cvWriteInt( fs, "nactive_vars", (int)cvSum(active_var_mask).val[0] );
+ cvWriteReal( fs, "oob_error", oob_error );
+
+ if( var_importance )
+ cvWrite( fs, "var_importance", var_importance );
+
+ cvWriteInt( fs, "ntrees", ntrees );
+
+ data->write_params( fs );
+
+ cvStartWriteStruct( fs, "trees", CV_NODE_SEQ );
+
+ for( k = 0; k < ntrees; k++ )
+ {
+ cvStartWriteStruct( fs, 0, CV_NODE_MAP );
+ trees[k]->write( fs );
+ cvEndWriteStruct( fs );
+ }
+
+ cvEndWriteStruct( fs ); //trees
+ cvEndWriteStruct( fs ); //CV_TYPE_NAME_ML_RTREES
+}
+
+
+void CvRTrees::read( CvFileStorage* fs, CvFileNode* fnode )
+{
+ int nactive_vars, var_count, k;
+ CvSeqReader reader;
+ CvFileNode* trees_fnode = 0;
+
+ clear();
+
+ nclasses = cvReadIntByName( fs, fnode, "nclasses", -1 );
+ nsamples = cvReadIntByName( fs, fnode, "nsamples" );
+ nactive_vars = cvReadIntByName( fs, fnode, "nactive_vars", -1 );
+ oob_error = cvReadRealByName(fs, fnode, "oob_error", -1 );
+ ntrees = cvReadIntByName( fs, fnode, "ntrees", -1 );
+
+ var_importance = (CvMat*)cvReadByName( fs, fnode, "var_importance" );
+
+ if( nclasses < 0 || nsamples <= 0 || nactive_vars < 0 || oob_error < 0 || ntrees <= 0)
+ CV_Error( CV_StsParseError, "Some <nclasses>, <nsamples>, <var_count>, "
+ "<nactive_vars>, <oob_error>, <ntrees> of tags are missing" );
+
+ rng = CvRNG( -1 );
+
+ trees = (CvForestTree**)cvAlloc( sizeof(trees[0])*ntrees );
+ memset( trees, 0, sizeof(trees[0])*ntrees );
+
+ data = new CvDTreeTrainData();
+ data->read_params( fs, fnode );
+ data->shared = true;
+
+ trees_fnode = cvGetFileNodeByName( fs, fnode, "trees" );
+ if( !trees_fnode || !CV_NODE_IS_SEQ(trees_fnode->tag) )
+ CV_Error( CV_StsParseError, "<trees> tag is missing" );
+
+ cvStartReadSeq( trees_fnode->data.seq, &reader );
+ if( reader.seq->total != ntrees )
+ CV_Error( CV_StsParseError,
+ "<ntrees> is not equal to the number of trees saved in file" );
+
+ for( k = 0; k < ntrees; k++ )
+ {
+ trees[k] = new CvForestTree();
+ trees[k]->read( fs, (CvFileNode*)reader.ptr, this, data );
+ CV_NEXT_SEQ_ELEM( reader.seq->elem_size, reader );
+ }
+
+ var_count = data->var_count;
+ active_var_mask = cvCreateMat( 1, var_count, CV_8UC1 );
+ {
+ // initialize active variables mask
+ CvMat submask1, submask2;
+ cvGetCols( active_var_mask, &submask1, 0, nactive_vars );
+ cvGetCols( active_var_mask, &submask2, nactive_vars, var_count );
+ cvSet( &submask1, cvScalar(1) );
+ cvZero( &submask2 );
+ }
+}
+
+
+int CvRTrees::get_tree_count() const
+{
+ return ntrees;
+}
+
+CvForestTree* CvRTrees::get_tree(int i) const
+{
+ return (unsigned)i < (unsigned)ntrees ? trees[i] : 0;
+}
+
+using namespace cv;
+
+bool CvRTrees::train( const Mat& _train_data, int _tflag,
+ const Mat& _responses, const Mat& _var_idx,
+ const Mat& _sample_idx, const Mat& _var_type,
+ const Mat& _missing_mask, CvRTParams _params )
+{
+ CvMat tdata = _train_data, responses = _responses, vidx = _var_idx,
+ sidx = _sample_idx, vtype = _var_type, mmask = _missing_mask;
+ return train(&tdata, _tflag, &responses, vidx.data.ptr ? &vidx : 0,
+ sidx.data.ptr ? &sidx : 0, vtype.data.ptr ? &vtype : 0,
+ mmask.data.ptr ? &mmask : 0, _params);
+}
+
+
+float CvRTrees::predict( const Mat& _sample, const Mat& _missing ) const
+{
+ CvMat sample = _sample, mmask = _missing;
+ return predict(&sample, mmask.data.ptr ? &mmask : 0);
+}
+
+float CvRTrees::predict_prob( const Mat& _sample, const Mat& _missing) const
+{
+ CvMat sample = _sample, mmask = _missing;
+ return predict_prob(&sample, mmask.data.ptr ? &mmask : 0);
+}
+
+
+// End of file.