[Regression] Add affine regression

apps/regression/Makefile

@@ -8,6 +8,7 @@ app_regression_test_src += $(addprefix apps/regression/,\
 )
 
 app_regression_test_src += $(addprefix apps/regression/model/,\
+  affine_model.cpp \
   cubic_model.cpp \
   exponential_model.cpp \
   linear_model.cpp \

apps/regression/base.de.i18n

@@ -10,6 +10,7 @@ ValueNotReachedByRegression = "Wert in diesem Fenster nicht erreicht"
 NumberOfDots = "Punktanzahl"
 Covariance = "Kovarianz"
 Linear = "Lineare"
+Affine = "Affine"
 Quadratic = "Quadratische"
 Cubic = "Kubische"
 Quartic = "Biquadratische"

apps/regression/base.en.i18n

@@ -10,6 +10,7 @@ ValueNotReachedByRegression = "Value not reached in this window"
 NumberOfDots = "Number of points"
 Covariance = "Covariance"
 Linear = "Linear"
+Affine = "Affine"
 Quadratic = "Quadratic"
 Cubic = "Cubic"
 Quartic = "Quartic"

apps/regression/base.es.i18n

@@ -10,6 +10,7 @@ ValueNotReachedByRegression = "Valor no alcanzado en esta ventana"
 NumberOfDots = "Número de puntos"
 Covariance = "Covarianza"
 Linear = "Lineal"
+Affine = "Affine"
 Quadratic = "Cuadrática"
 Cubic = "Cúbica"
 Quartic = "Cuártica"

apps/regression/base.fr.i18n

@@ -10,6 +10,7 @@ ValueNotReachedByRegression = "Valeur non atteinte dans cette fenêtre"
 NumberOfDots = "Nombre de points"
 Covariance = "Covariance"
 Linear = "Linéaire"
+Affine = "Affine"
 Quadratic = "Quadratique"
 Cubic = "Cubique"
 Quartic = "Quartique"

apps/regression/base.pt.i18n

@@ -10,6 +10,7 @@ ValueNotReachedByRegression = "Valor não alcançado nesta janela"
 NumberOfDots = "Número de pontos"
 Covariance = "Covariancia"
 Linear = "Linear"
+Affine = "Affine"
 Quadratic = "Quadrática"
 Cubic = "Cúbica"
 Quartic = "Quarto grau"

apps/regression/base.universal.i18n

@@ -1,3 +1,4 @@
+AffineRegressionFormula  = " y=a·x "
 QuadraticRegressionFormula  = " y=a·x^2+b·x+c "
 CubicRegressionFormula  = " y=a·x^3+b·x^2+c·x+d "
 QuarticRegressionFormula  = " y=a·x^4+b·x^3+c·x^2+d·x+e "

apps/regression/graph_controller.cpp

@@ -187,14 +187,15 @@ void GraphController::reloadBannerView() {
     coefficientName++;
   }
 
-  if (m_store->seriesRegressionType(*m_selectedSeriesIndex) == Model::Type::Linear) {
+  if (m_store->seriesRegressionType(*m_selectedSeriesIndex) == Model::Type::Linear || m_store->seriesRegressionType(*m_selectedSeriesIndex) == Model::Type::Affine) {
+    int index = model->numberOfCoefficients();
     // Set "r=..."
     numberOfChar = 0;
     legend = " r=";
     double r = m_store->correlationCoefficient(*m_selectedSeriesIndex);
     numberOfChar += strlcpy(buffer, legend, bufferSize);
     numberOfChar += PoincareHelpers::ConvertFloatToText<double>(r, buffer + numberOfChar, bufferSize - numberOfChar, Preferences::LargeNumberOfSignificantDigits);
-    m_bannerView.subTextAtIndex(2)->setText(buffer);
+    m_bannerView.subTextAtIndex(0+index)->setText(buffer);
 
     // Set "r2=..."
     numberOfChar = 0;
@@ -202,11 +203,11 @@ void GraphController::reloadBannerView() {
     double r2 = m_store->squaredCorrelationCoefficient(*m_selectedSeriesIndex);
     numberOfChar += strlcpy(buffer, legend, bufferSize);
     numberOfChar += PoincareHelpers::ConvertFloatToText<double>(r2, buffer + numberOfChar, bufferSize - numberOfChar, Preferences::LargeNumberOfSignificantDigits);
-    m_bannerView.subTextAtIndex(3)->setText(buffer);
+    m_bannerView.subTextAtIndex(1+index)->setText(buffer);
 
     // Clean the last subview
     buffer[0] = 0;
-    m_bannerView.subTextAtIndex(4)->setText(buffer);
+    m_bannerView.subTextAtIndex(2+index)->setText(buffer);
 
   } else {
     // Empty all non used subviews

apps/regression/model/affine_model.cpp

@@ -0,0 +1,51 @@
+#include "affine_model.h"
+#include "../store.h"
+#include <poincare/layout_helper.h>
+#include <math.h>
+#include <assert.h>
+
+using namespace Poincare;
+
+namespace Regression {
+
+Layout AffineModel::layout() {
+  if (m_layout.isUninitialized()) {
+    const char * s = "a·X";
+    m_layout = LayoutHelper::String(s, strlen(s), k_layoutFont);
+  }
+  return m_layout;
+}
+
+double AffineModel::evaluate(double * modelCoefficients, double x) const {
+  double a = modelCoefficients[0];
+  return a*x;
+}
+
+double AffineModel::levelSet(double * modelCoefficients, double xMin, double step, double xMax, double y, Poincare::Context * context) {
+  double a = modelCoefficients[0];
+  double b = modelCoefficients[1];
+  if (a == 0) {
+    return NAN;
+  }
+  return y-b;
+}
+
+void AffineModel::fit(Store * store, int series, double * modelCoefficients, Poincare::Context * context) {
+  modelCoefficients[0] = store->slope(series);
+  modelCoefficients[1] = store->yIntercept(series);
+}
+
+double AffineModel::partialDerivate(double * modelCoefficients, int derivateCoefficientIndex, double x) const {
+  if (derivateCoefficientIndex == 0) {
+    // Derivate: x
+    return x;
+  }
+  if (derivateCoefficientIndex == 1) {
+    // Derivate: 1;
+    return 1;
+  }
+  assert(false);
+  return 0.0;
+}
+
+}

apps/regression/model/affine_model.h

@@ -0,0 +1,24 @@
+#ifndef REGRESSION_AFFINE_MODEL_H
+#define REGRESSION_AFFINE_MODEL_H
+
+#include "model.h"
+
+namespace Regression {
+
+class AffineModel : public Model {
+public:
+  using Model::Model;
+  Poincare::Layout layout() override;
+  I18n::Message formulaMessage() const override { return I18n::Message::AffineRegressionFormula; }
+  double evaluate(double * modelCoefficients, double x) const override;
+  double levelSet(double * modelCoefficients, double xMin, double step, double xMax, double y, Poincare::Context * context) override;
+  void fit(Store * store, int series, double * modelCoefficients, Poincare::Context * context) override;
+  double partialDerivate(double * modelCoefficients, int derivateCoefficientIndex, double x) const override;
+  int numberOfCoefficients() const override { return 1; }
+  int bannerLinesCount() const override { return 2; }
+};
+
+}
+
+
+#endif

apps/regression/model/model.h

@@ -15,16 +15,17 @@ class Model {
 public:
   enum class Type : uint8_t {
     Linear      = 0,
-    Quadratic   = 1,
-    Cubic       = 2,
-    Quartic     = 3,
-    Logarithmic = 4,
-    Exponential = 5,
-    Power       = 6,
-    Trigonometric = 7,
-    Logistic    = 8
+    Affine      = 1,
+    Quadratic   = 2,
+    Cubic       = 3,
+    Quartic     = 4,
+    Logarithmic = 5,
+    Exponential = 6,
+    Power       = 7,
+    Trigonometric = 8,
+    Logistic    = 9
   };
-  static constexpr int k_numberOfModels = 9;
+  static constexpr int k_numberOfModels = 10;
   static constexpr int k_maxNumberOfCoefficients = 5; // This has to verify: k_maxNumberOfCoefficients < Matrix::k_maxNumberOfCoefficients
   virtual ~Model() = default;
   virtual Poincare::Layout layout() = 0;

apps/regression/regression_controller.cpp

@@ -82,7 +82,7 @@ HighlightCell * RegressionController::reusableCell(int index, int type) {
 void RegressionController::willDisplayCellAtLocation(HighlightCell * cell, int i, int j) {
   assert(i == 0);
   assert(j >= 0 && j < k_numberOfRows);
-  I18n::Message messages[k_numberOfRows] = {I18n::Message::Linear, I18n::Message::Quadratic, I18n::Message::Cubic, I18n::Message::Quartic, I18n::Message::Logarithmic, I18n::Message::Exponential, I18n::Message::Power, I18n::Message::Trigonometrical, I18n::Message::Logistic};
+  I18n::Message messages[k_numberOfRows] = {I18n::Message::Linear, I18n::Message::Affine, I18n::Message::Quadratic, I18n::Message::Cubic, I18n::Message::Quartic, I18n::Message::Logarithmic, I18n::Message::Exponential, I18n::Message::Power, I18n::Message::Trigonometrical, I18n::Message::Logistic};
   MessageTableCellWithExpression * castedCell = static_cast<MessageTableCellWithExpression *>(cell);
   castedCell->setMessage(messages[j]);
   castedCell->setLayout(m_store->regressionModel((Model::Type) j)->layout());

apps/regression/regression_controller.h

@@ -31,7 +31,7 @@ public:
   int numberOfRows() const override { return k_numberOfRows; }
   void willDisplayCellAtLocation(HighlightCell * cell, int i, int j) override;
 private:
-  constexpr static int k_numberOfRows = 9;
+  constexpr static int k_numberOfRows = 10;
   constexpr static int k_numberOfCells = 6; // (240 - 70) / 35
   MessageTableCellWithExpression m_regressionCells[k_numberOfCells];
   SelectableTableView m_selectableTableView;

apps/regression/store.cpp

@@ -11,7 +11,7 @@ using namespace Shared;
 
 namespace Regression {
 
-static_assert(Model::k_numberOfModels == 9, "Number of models changed, Regression::Store() needs to adapt");
+static_assert(Model::k_numberOfModels == 10, "Number of models changed, Regression::Store() needs to adapt");
 static_assert(Store::k_numberOfSeries == 3, "Number of series changed, Regression::Store() needs to adapt (m_seriesChecksum)");
 
 Store::Store() :
@@ -285,7 +285,7 @@ double Store::squaredCorrelationCoefficient(int series) const {
 }
 
 Model * Store::regressionModel(int index) {
-  Model * models[Model::k_numberOfModels] = {&m_linearModel, &m_quadraticModel, &m_cubicModel, &m_quarticModel, &m_logarithmicModel, &m_exponentialModel, &m_powerModel, &m_trigonometricModel, &m_logisticModel};
+  Model * models[Model::k_numberOfModels] = {&m_linearModel, &m_affineModel, &m_quadraticModel, &m_cubicModel, &m_quarticModel, &m_logarithmicModel, &m_exponentialModel, &m_powerModel, &m_trigonometricModel, &m_logisticModel};
   return models[index];
 }
 

apps/regression/store.h

@@ -11,6 +11,7 @@
 #include "model/quadratic_model.h"
 #include "model/quartic_model.h"
 #include "model/trigonometric_model.h"
+#include "model/affine_model.h"
 #include "../shared/interactive_curve_view_range.h"
 #include "../shared/double_pair_store.h"
 #include <escher/responder.h>
@@ -79,6 +80,7 @@ private:
   uint32_t m_seriesChecksum[k_numberOfSeries];
   Model::Type m_regressionTypes[k_numberOfSeries];
   LinearModel m_linearModel;
+  AffineModel m_affineModel;
   QuadraticModel m_quadraticModel;
   CubicModel m_cubicModel;
   QuarticModel m_quarticModel;