[apps/regression] Fill column with formula

apps/regression/Makefile

@@ -16,6 +16,7 @@ app_objs += $(addprefix apps/regression/,\
   prediction_parameter_controller.o\
   store.o\
   store_controller.o\
+  regression_context.o\
 )
 
 i18n_files += $(addprefix apps/regression/,\

apps/regression/regression_context.cpp

@@ -0,0 +1,37 @@
+#include "regression_context.h"
+#include <poincare/decimal.h>
+#include <assert.h>
+#include <string.h>
+
+using namespace Poincare;
+using namespace Shared;
+
+namespace Regression {
+
+void RegressionContext::setExpressionForSymbolName(const Expression * expression, const Symbol * symbol, Context & context) {
+  m_parentContext->setExpressionForSymbolName(expression, symbol, context);
+}
+
+const Expression * RegressionContext::expressionForSymbol(const Symbol * symbol) {
+  if (Symbol::isRegressionSymbol(symbol->name())) {
+    const char * seriesName = Symbol::textForSpecialSymbols(symbol->name());
+    assert(strlen(seriesName) == 2);
+
+    int series = (int)(seriesName[1] - '0') - 1;
+    assert(series >= 0 && series < FloatPairStore::k_numberOfSeries);
+
+    assert((seriesName[0] == 'X') || (seriesName[0] == 'Y'));
+    int storeI = seriesName[0] == 'X' ? 0 : 1;
+
+    assert(m_seriesPairIndex >= 0);
+    assert(m_seriesPairIndex < m_store->numberOfPairsOfSeries(series));
+
+    Expression * result = new Decimal(m_store->get(series, storeI, m_seriesPairIndex));
+    assert(result != nullptr);
+    return result;
+  } else {
+    return m_parentContext->expressionForSymbol(symbol);
+  }
+}
+
+}

apps/regression/regression_context.h

@@ -0,0 +1,28 @@
+#ifndef REGRESSION_REGRESSION_CONTEXT_H
+#define REGRESSION_REGRESSION_CONTEXT_H
+
+#include <poincare/context.h>
+#include "../shared/float_pair_store.h"
+
+namespace Regression {
+
+class RegressionContext : public Poincare::Context {
+public:
+  RegressionContext(Shared::FloatPairStore * store, Poincare::Context * parentContext = nullptr) :
+    Poincare::Context(),
+    m_store(store),
+    m_seriesPairIndex(-1),
+    m_parentContext(parentContext)
+  {}
+  void setSeriesPairIndex(int j) { m_seriesPairIndex = j; }
+  void setExpressionForSymbolName(const Poincare::Expression * expression, const Poincare::Symbol * symbol, Poincare::Context & context) override;
+  const Poincare::Expression * expressionForSymbol(const Poincare::Symbol * symbol) override;
+private:
+  Shared::FloatPairStore * m_store;
+  int m_seriesPairIndex;
+  Poincare::Context * m_parentContext;
+};
+
+}
+
+#endif

apps/regression/store_controller.cpp

@@ -1,5 +1,6 @@
 #include "store_controller.h"
 #include "app.h"
+#include "regression_context.h"
 #include "../apps_container.h"
 #include "../constant.h"
 #include "../../poincare/src/layout/char_layout.h"
@@ -18,6 +19,47 @@ StoreController::StoreController(Responder * parentResponder, Store * store, But
 {
 }
 
+void StoreController::setFormulaLabel() {
+  int series = selectedColumn() / Store::k_numberOfColumnsPerSeries;
+  int isXColumn = selectedColumn() % Store::k_numberOfColumnsPerSeries == 0;
+  char text[] = {isXColumn ? 'X' : 'Y', static_cast<char>('1' + series), '=', 0};
+  static_cast<ContentView *>(view())->formulaInputView()->setBufferText(text);
+}
+
+void StoreController::fillColumnWithFormula(Expression * formula) {
+  int currentColumn = selectedColumn();
+  // Fetch the series used in the formula to compute the size of the filled in series
+  char variables[7] = {0, 0, 0, 0, 0, 0, 0};
+  formula->getVariables(Symbol::isRegressionSymbol, variables);
+  int numberOfValuesToCompute = -1;
+  int index = 0;
+  while (variables[index] != 0) {
+    const char * seriesName = Symbol::textForSpecialSymbols(variables[index]);
+    assert(strlen(seriesName) == 2);
+    int series = (int)(seriesName[1] - '0') - 1;
+    assert(series >= 0 && series < FloatPairStore::k_numberOfSeries);
+    if (numberOfValuesToCompute == -1) {
+      numberOfValuesToCompute = m_store->numberOfPairsOfSeries(series);
+    } else {
+      numberOfValuesToCompute = min(numberOfValuesToCompute, m_store->numberOfPairsOfSeries(series));
+    }
+    index++;
+  }
+  if (numberOfValuesToCompute == -1) {
+    numberOfValuesToCompute = m_store->numberOfPairsOfSeries(selectedColumn()/FloatPairStore::k_numberOfColumnsPerSeries);
+  }
+
+  RegressionContext regressionContext(m_store, const_cast<AppsContainer *>(static_cast<const AppsContainer *>(app()->container()))->globalContext());
+  for (int j = 0; j < numberOfValuesToCompute; j++) {
+    // Set the context
+    regressionContext.setSeriesPairIndex(j);
+    // Compute the new value using the formula
+    double evaluation = formula->approximateToScalar<double>(regressionContext);
+    setDataAtLocation(evaluation, currentColumn, j + 1);
+  }
+  selectableTableView()->reloadData();
+}
+
 void StoreController::willDisplayCellAtLocation(HighlightCell * cell, int i, int j) {
   ::StoreController::willDisplayCellAtLocation(cell, i, j);
   if (cellAtLocationIsEditable(i, j)) {

apps/regression/store_controller.h

@@ -11,8 +11,8 @@ namespace Regression {
 class StoreController : public Shared::StoreController {
 public:
   StoreController(Responder * parentResponder, Store * store, ButtonRowController * header);
-  void setFormulaLabel() override {} //TODO
-  void fillColumnWithFormula(Poincare::Expression * formula) override {} //TODO
+  void setFormulaLabel() override;
+  void fillColumnWithFormula(Poincare::Expression * formula) override;
   void willDisplayCellAtLocation(HighlightCell * cell, int i, int j) override;
 private:
   HighlightCell * titleCells(int index) override;