#3281 Add weighted geometric mean calculator

ApplicationCode/Application/Tools/RiaWeightedGeometricMeanCalculator.cpp

@@ -0,0 +1,65 @@
+/////////////////////////////////////////////////////////////////////////////////
+//
+//  Copyright (C) 2018-     Statoil ASA
+//
+//  ResInsight is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  ResInsight is distributed in the hope that it will be useful, but WITHOUT ANY
+//  WARRANTY; without even the implied warranty of MERCHANTABILITY or
+//  FITNESS FOR A PARTICULAR PURPOSE.
+//
+//  See the GNU General Public License at <http://www.gnu.org/licenses/gpl.html>
+//  for more details.
+//
+/////////////////////////////////////////////////////////////////////////////////
+
+#include "RiaWeightedGeometricMeanCalculator.h"
+
+#include "cvfAssert.h"
+
+#include <cmath>
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+RiaWeightedGeometricMeanCalculator::RiaWeightedGeometricMeanCalculator()
+    : m_aggregatedWeightedValue(1.0)
+    , m_aggregatedWeight(0.0)
+{
+}
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+void RiaWeightedGeometricMeanCalculator::addValueAndWeight(double value, double weight)
+{
+    CVF_ASSERT(weight >= 0.0);
+
+    // This can be a very big number, consider other algorithms if that becomes a problem
+    m_aggregatedWeightedValue *= std::pow(value,  weight);
+    m_aggregatedWeight += weight;
+}
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+double RiaWeightedGeometricMeanCalculator::weightedMean() const
+{
+    if (m_aggregatedWeight > 1e-7)
+    {
+        return std::pow(m_aggregatedWeightedValue, 1 / m_aggregatedWeight);
+    }
+
+    return 0.0;
+}
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+double RiaWeightedGeometricMeanCalculator::aggregatedWeight() const
+{
+    return m_aggregatedWeight;
+}