Reserve vector - to minimize reallocation costs

Reserving vector to save on reallocation costs, where we know the size in advance.
qgis · Jan 30, 2019 · 4559d9e · 4559d9e
1 parent 2e92dab
commit 4559d9e
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/src/analysis/mesh/qgsmeshcalculator.cpp b/src/analysis/mesh/qgsmeshcalculator.cpp
@@ -153,7 +153,11 @@ QgsMeshCalculator::Result QgsMeshCalculator::processCalculation( QgsFeedback *fe
   QVector<QgsMeshDataBlock> datasetActive;
   QVector<double> times;
 
-  for ( int i = 0; i < outputGroup->datasets.size(); ++i )
+  const auto datasize = outputGroup->datasets.size();
+  datasetValues.reserve( datasize );
+  times.reserve( datasize );
+
+  for ( int i = 0; i < datasize; ++i )
   {
     const std::shared_ptr<QgsMeshMemoryDataset> dataset = outputGroup->datasets.at( i );