[apps/reg] Prevent fitting when data not suitable

apps/regression/calculation_controller.cpp

@@ -84,10 +84,7 @@ void CalculationController::tableViewDidChangeSelection(SelectableTableView * t,
 }
 
 bool CalculationController::isEmpty() const {
-  if (m_store->numberOfPairs() == 0) {
-    return true;
-  }
-  return false;
+  return m_store->isEmpty();
 }
 
 I18n::Message CalculationController::emptyMessage() {

apps/regression/graph_controller.cpp

@@ -27,22 +27,11 @@ ViewController * GraphController::initialisationParameterController() {
 }
 
 bool GraphController::isEmpty() const {
-  if (m_store->isEmpty()) {
-    return true;
-  }
-  for (int series = 0; series < DoublePairStore::k_numberOfSeries; series++) {
-    if (!m_store->seriesIsEmpty(series) && !std::isinf(m_store->slope(series)) && !std::isnan(m_store->slope(series))) {
-      return false;
-    }
-  }
-  return true;
+  return m_store->isEmpty();
 }
 
 I18n::Message GraphController::emptyMessage() {
-  if (m_store->numberOfPairs() == 0) {
-    return I18n::Message::NoDataToPlot;
-  }
-  return I18n::Message::NoEnoughDataForRegression;
+  return I18n::Message::NoDataToPlot;
 }
 
 void GraphController::viewWillAppear() {

apps/regression/model/logarithmic_model.cpp

@@ -1,4 +1,5 @@
 #include "logarithmic_model.h"
+#include "../store.h"
 #include <math.h>
 #include <poincare/layout_engine.h>
 #include <assert.h>
@@ -35,6 +36,7 @@ double LogarithmicModel::levelSet(double * modelCoefficients, double y) const {
 double LogarithmicModel::partialDerivate(double * modelCoefficients, int derivateCoefficientIndex, double x) const {
   if (derivateCoefficientIndex == 0) {
     // Derivate: ln(x)
+    assert(x >0);
     return log(x);
   }
   if (derivateCoefficientIndex == 1) {
@@ -45,4 +47,17 @@ double LogarithmicModel::partialDerivate(double * modelCoefficients, int derivat
   return 0.0;
 }
 
+bool LogarithmicModel::dataSuitableForFit(Store * store, int series) const {
+  if (!Model::dataSuitableForFit(store, series)) {
+    return false;
+  }
+  int numberOfPairs = store->numberOfPairsOfSeries(series);
+  for (int j = 0; j < numberOfPairs; j++) {
+    if (store->get(series, 0, j) <= 0) {
+      return false;
+    }
+  }
+  return true;
+}
+
 }

apps/regression/model/logarithmic_model.h

@@ -16,6 +16,8 @@ public:
   double levelSet(double * modelCoefficients, double y) const override;
   double partialDerivate(double * modelCoefficients, int derivateCoefficientIndex, double x) const override;
   int numberOfCoefficients() const override { return 2; }
+protected:
+  virtual bool dataSuitableForFit(Store * store, int series) const override;
 };
 
 }

apps/regression/model/model.cpp

@@ -11,7 +11,17 @@ using namespace Shared;
 namespace Regression {
 
 void Model::fit(Store * store, int series, double * modelCoefficients, Poincare::Context * context) {
-  fitLevenbergMarquardt(store, series, modelCoefficients, context);
+  if (dataSuitableForFit(store, series)) {
+    fitLevenbergMarquardt(store, series, modelCoefficients, context);
+  } else {
+    for (int i = 0; i < numberOfCoefficients(); i++) {
+      modelCoefficients[i] = NAN; //TODO undef /inf ?
+    }
+  }
+}
+
+bool Model::dataSuitableForFit(Store * store, int series) const {
+  return !store->seriesIsEmpty(series) && !std::isinf(store->slope(series)) && !std::isnan(store->slope(series));
 }
 
 void Model::fitLevenbergMarquardt(Store * store, int series, double * modelCoefficients, Context * context) {

apps/regression/model/model.h

@@ -33,6 +33,9 @@ public:
   virtual double levelSet(double * modelCoefficients, double y) const = 0;
   virtual void fit(Store * store, int series, double * modelCoefficients, Poincare::Context * context);
   virtual int numberOfCoefficients() const = 0;
+protected:
+  // Fit
+  virtual bool dataSuitableForFit(Store * store, int series) const;
 private:
   // Model attributes
   virtual double partialDerivate(double * modelCoefficients, int derivateCoefficientIndex, double x) const = 0;

apps/regression/model/power_model.cpp

@@ -1,4 +1,5 @@
 #include "power_model.h"
+#include "../store.h"
 #include <math.h>
 #include <assert.h>
 #include "../../poincare/include/poincare_layouts.h"
@@ -66,4 +67,18 @@ double PowerModel::partialDerivate(double * modelCoefficients, int derivateCoeff
   return 0.0;
 }
 
+bool PowerModel::dataSuitableForFit(Store * store, int series) const {
+  if (!Model::dataSuitableForFit(store, series)) {
+    return false;
+  }
+  int numberOfPairs = store->numberOfPairsOfSeries(series);
+  for (int j = 0; j < numberOfPairs; j++) {
+    if (store->get(series, 0, j) < 0) {
+      return false;
+    }
+  }
+  return true;
+}
+
+
 }

apps/regression/model/power_model.h

@@ -16,6 +16,8 @@ public:
   double levelSet(double * modelCoefficients, double y) const override;
   double partialDerivate(double * modelCoefficients, int derivateCoefficientIndex, double x) const override;
   int numberOfCoefficients() const override { return 2; }
+protected:
+  virtual bool dataSuitableForFit(Store * store, int series) const override;
 };
 
 }