fix incorrect zero comparison of floating point vars (#911)

src/artm/core/collection_parser.cc

@@ -205,7 +205,7 @@ CollectionParserInfo CollectionParser::ParseDocwordBagOfWordsUci(TokenMap* token
       BOOST_THROW_EXCEPTION(ArgumentOutOfRangeException("wordID", token_id, ss.str()));
     }
 
-    if (token_weight == 0.0f) {
+    if (isZero(token_weight)) {
       token_weight_zero++;
       continue;
     }

src/artm/core/helpers.cc

@@ -244,5 +244,13 @@ void Helpers::SaveMessage(const std::string& full_filename,
   fout.close();
 }
 
+bool isZero(double value, double tol) {
+  return std::abs(value) < tol;
+}
+
+bool isZero(float value, float tol) {
+  return std::abs(value) < tol;
+}
+
 }  // namespace core
 }  // namespace artm

src/artm/core/helpers.h

@@ -58,5 +58,9 @@ class Helpers {
                           const ::google::protobuf::Message& message);
 };
 
+bool isZero(double value, double tol = 1e-37);
+
+bool isZero(float value, float tol = 1e-16f);
+
 }  // namespace core
 }  // namespace artm

src/artm/core/processor_transaction_helpers.cc

@@ -190,15 +190,15 @@ void ProcessorTransactionHelpers::TransactionInferThetaAndUpdateNwtSparse(
           }
         }
 
-        float p_dx_val = 0;
+        float p_dx_val = 0.0f;
         for (int k = 0; k < num_topics; ++k) {
           p_dx_val += p_xt_local[k] * theta_ptr[k];
         }
-        if (p_dx_val == 0) {
+        if (isZero(p_dx_val)) {
           continue;
         }
 
-        const float alpha = sparse_ndx.val()[i] / p_dx_val;
+        const double alpha = sparse_ndx.val()[i] / p_dx_val;
         for (int k = 0; k < num_topics; ++k) {
           ntd_ptr[k] += alpha * p_xt_local[k];
         }
@@ -243,7 +243,7 @@ void ProcessorTransactionHelpers::TransactionInferThetaAndUpdateNwtSparse(
     for (int i = sparse_nxd.row_ptr()[transaction_index]; i < sparse_nxd.row_ptr()[transaction_index + 1]; ++i) {
       int d = sparse_nxd.col_ind()[i];
       float p_xd_val = blas->sdot(num_topics, &p_xt_local[0], 1, &(*theta_matrix)(0, d), 1);  // NOLINT
-      if (p_xd_val == 0) {
+      if (isZero(p_xd_val)) {
         continue;
       }
 

src/artm/score/perplexity.cc

@@ -9,6 +9,7 @@
 #include <sstream>
 
 #include "artm/core/exceptions.h"
+#include "artm/core/helpers.h"
 #include "artm/core/protobuf_helpers.h"
 
 #include "artm/score/perplexity.h"
@@ -145,7 +146,7 @@ void Perplexity::AppendScore(
     }
 
     float token_weight = tt_weight * item.token_weight(token_index);
-    if (token_weight == 0.0f) {
+    if (core::isZero(token_weight)) {
       continue;
     }
 
@@ -167,7 +168,7 @@ void Perplexity::AppendScore(
       sum += theta[topic_index] * phi_values[topic_index];
     }
 
-    if (sum == 0.0f) {
+    if (core::isZero(sum)) {
       if (use_document_unigram_model) {
         sum = token_weight / (use_tt ? normalizer_map[tt] : normalizer);
       } else {

src/bigartm/srcmain.cc

@@ -1,12 +1,15 @@
 // Copyright 2018, Additive Regularization of Topic Models.
 
 #include <stdlib.h>
+
+#include <cstring>
+#include <ctime>
+#include <cmath>
+
 #include <algorithm>
 #include <chrono>
-#include <ctime>
 #include <fstream>
 #include <future>
-#include <cstring>
 #include <iostream>
 #include <iomanip>
 #include <set>
@@ -1338,7 +1341,7 @@ int execute(const artm_options& options, int argc, char* argv[]) {
     }
 
     master_config.add_class_id(class_id.first);
-    master_config.add_class_weight(class_id.second == 0.0f ? 1.0f : class_id.second);
+    master_config.add_class_weight(std::abs(class_id.second) < 1e-16 ? 1.0f : class_id.second);
   }
 
   master_config.set_opt_for_avx(!options.b_disable_avx_opt);