[apps][poincare] Add matrix variables M0-M9

Change-Id: I09d82633ac9ffafc616c2be1e16575f2a5b730f7
2026-01-19 00:37:25 +01:00 · 2017-06-06 13:23:31 +02:00
parent ba73e259ad
commit d07ba2dc7c
11 changed files with 191 additions and 35 deletions
--- a/apps/math_toolbox.cpp
+++ b/apps/math_toolbox.cpp
@@ -13,14 +13,18 @@ const ToolboxNode probabilityChildren[2] = {ToolboxNode(I18n::Message::BinomialC
 const ToolboxNode arithmeticChildren[4] = {ToolboxNode(I18n::Message::GcdCommandWithArg, I18n::Message::GreatCommonDivisor, I18n::Message::GcdCommand),ToolboxNode(I18n::Message::LcmCommandWithArg, I18n::Message::LeastCommonMultiple, I18n::Message::LcmCommand), ToolboxNode(I18n::Message::RemCommandWithArg, I18n::Message::Remainder, I18n::Message::RemCommand), ToolboxNode(I18n::Message::QuoCommandWithArg, I18n::Message::Quotient, I18n::Message::QuoCommand)};
 #if MATRICES_ARE_DEFINED
 const ToolboxNode matricesChildren[5] = {ToolboxNode(I18n::Message::InverseCommandWithArg, I18n::Message::Inverse, I18n::Message::InverseCommand), ToolboxNode(I18n::Message::DeterminantCommandWithArg, I18n::Message::Determinant, I18n::Message::DeterminantCommand), ToolboxNode(I18n::Message::TransposeCommandWithArg, I18n::Message::Transpose, I18n::Message::TransposeCommand), ToolboxNode(I18n::Message::TraceCommandWithArg, I18n::Message::Trace, I18n::Message::TraceCommand), ToolboxNode(I18n::Message::DimensionCommandWithArg, I18n::Message::Dimension, I18n::Message::DimensionCommand)};
+#endif
+#if LIST_ARE_DEFINED
 const ToolboxNode listesChildren[5] = {ToolboxNode(I18n::Message::SortCommandWithArg, I18n::Message::Sort, I18n::Message::SortCommand), ToolboxNode(I18n::Message::InvSortCommandWithArg, I18n::Message::InvSort, I18n::Message::InvSortCommand), ToolboxNode(I18n::Message::MaxCommandWithArg, I18n::Message::Maximum, I18n::Message::MaxCommand), ToolboxNode(I18n::Message::MinCommandWithArg, I18n::Message::Minimum, I18n::Message::MinCommand), ToolboxNode(I18n::Message::DimensionCommandWithArg, I18n::Message::Dimension, I18n::Message::DimensionCommand)};
 #endif
 const ToolboxNode approximationChildren[4] = {ToolboxNode(I18n::Message::FloorCommandWithArg, I18n::Message::Floor, I18n::Message::FloorCommand), ToolboxNode(I18n::Message::FracCommandWithArg, I18n::Message::FracPart, I18n::Message::FracCommand), ToolboxNode(I18n::Message::CeilCommandWithArg, I18n::Message::Ceiling, I18n::Message::CeilCommand), ToolboxNode(I18n::Message::RoundCommandWithArg, I18n::Message::Rounding, I18n::Message::RoundCommand)};
 const ToolboxNode trigonometryChildren[6] = {ToolboxNode(I18n::Message::CoshCommandWithArg, I18n::Message::Cosh, I18n::Message::CoshCommand), ToolboxNode(I18n::Message::SinhCommandWithArg, I18n::Message::Sinh, I18n::Message::SinhCommand), ToolboxNode(I18n::Message::TanhCommandWithArg, I18n::Message::Tanh, I18n::Message::TanhCommand), ToolboxNode(I18n::Message::AcoshCommandWithArg, I18n::Message::Acosh, I18n::Message::AcoshCommand), ToolboxNode(I18n::Message::AsinhCommandWithArg, I18n::Message::Asinh, I18n::Message::AsinhCommand), ToolboxNode(I18n::Message::AtanhCommandWithArg, I18n::Message::Atanh, I18n::Message::AtanhCommand)};
 const ToolboxNode predictionChildren[3] = {ToolboxNode(I18n::Message::Prediction95CommandWithArg, I18n::Message::Prediction95, I18n::Message::Prediction95Command), ToolboxNode(I18n::Message::PredictionCommandWithArg, I18n::Message::Prediction, I18n::Message::PredictionCommand), ToolboxNode(I18n::Message::ConfidenceCommandWithArg, I18n::Message::Confidence, I18n::Message::ConfidenceCommand)};

-#if MATRICES_ARE_DEFINED
+#if LIST_ARE_DEFINED
 const ToolboxNode menu[12] = {ToolboxNode(I18n::Message::AbsCommandWithArg, I18n::Message::AbsoluteValue, I18n::Message::AbsCommand),
+#elif MATRICES_ARE_DEFINED
+const ToolboxNode menu[11] = {ToolboxNode(I18n::Message::AbsCommandWithArg, I18n::Message::AbsoluteValue, I18n::Message::AbsCommand),
 #else
 const ToolboxNode menu[10] = {ToolboxNode(I18n::Message::AbsCommandWithArg, I18n::Message::AbsoluteValue, I18n::Message::AbsCommand),
 #endif
@@ -32,13 +36,17 @@ const ToolboxNode menu[10] = {ToolboxNode(I18n::Message::AbsCommandWithArg, I18n
  ToolboxNode(I18n::Message::Arithmetic, I18n::Message::Default, I18n::Message::Default, arithmeticChildren, 4),
 #if MATRICES_ARE_DEFINED
  ToolboxNode(I18n::Message::Matrices,  I18n::Message::Default, I18n::Message::Default, matricesChildren, 5),
+#endif
+#if LIST_ARE_DEFINED
  ToolboxNode(I18n::Message::Lists, I18n::Message::Default, I18n::Message::Default, listesChildren, 5),
 #endif
  ToolboxNode(I18n::Message::Approximation, I18n::Message::Default, I18n::Message::Default, approximationChildren, 4),
  ToolboxNode(I18n::Message::HyperbolicTrigonometry, I18n::Message::Default, I18n::Message::Default, trigonometryChildren, 6),
  ToolboxNode(I18n::Message::Fluctuation, I18n::Message::Default, I18n::Message::Default, predictionChildren, 3)};
-#if MATRICES_ARE_DEFINED
+#if LIST_ARE_DEFINED
 const ToolboxNode toolboxModel = ToolboxNode(I18n::Message::Toolbox, I18n::Message::Default, I18n::Message::Default, menu, 12);
+#elif MATRICES_ARE_DEFINED
+const ToolboxNode toolboxModel = ToolboxNode(I18n::Message::Toolbox, I18n::Message::Default, I18n::Message::Default, menu, 11);
 #else
 const ToolboxNode toolboxModel = ToolboxNode(I18n::Message::Toolbox, I18n::Message::Default, I18n::Message::Default, menu, 10);
 #endif
--- a/apps/math_toolbox.h
+++ b/apps/math_toolbox.h
@@ -1,6 +1,7 @@
 #ifndef APPS_MATH_TOOLBOX_H
 #define APPS_MATH_TOOLBOX_H

+#define MATRICES_ARE_DEFINED 1
 #include <escher.h>
 #include "toolbox_node.h"

--- a/apps/variable_box_controller.cpp
+++ b/apps/variable_box_controller.cpp
@@ -32,7 +32,7 @@ void VariableBoxController::ContentViewController::didBecomeFirstResponder() {
 }

 bool VariableBoxController::ContentViewController::handleEvent(Ion::Events::Event event) {
-#if MATRIX_LIST_VARIABLES
+#if MATRIX_VARIABLES
  if (event == Ion::Events::Back && m_currentPage == Page::RootMenu) {
 #else
  if (event == Ion::Events::Back && m_currentPage == Page::Scalar) {
@@ -43,17 +43,19 @@ bool VariableBoxController::ContentViewController::handleEvent(Ion::Events::Even
  }
  if (event == Ion::Events::Back || event == Ion::Events::Left) {
    m_firstSelectedRow = m_previousSelectedRow;
-#if MATRIX_LIST_VARIABLES
+#if MATRIX_VARIABLES
+    m_selectableTableView.deselectTable();
    m_currentPage = Page::RootMenu;
 #endif
    app()->setFirstResponder(this);
    return true;
  }
  if (event == Ion::Events::OK || event == Ion::Events::EXE || (event == Ion::Events::Right && m_currentPage == Page::RootMenu)) {
-   if (m_currentPage == Page::RootMenu) {
+  if (m_currentPage == Page::RootMenu) {
      m_previousSelectedRow = selectedRow();
      m_firstSelectedRow = 0;
-      m_currentPage = pageAtIndex(selectedRow());
+      m_selectableTableView.deselectTable();
+      m_currentPage = pageAtIndex(m_previousSelectedRow);
      app()->setFirstResponder(this);
      return true;
    }
@@ -66,7 +68,8 @@ bool VariableBoxController::ContentViewController::handleEvent(Ion::Events::Even
    }
    m_textFieldCaller->insertTextAtLocation(editedText, m_textFieldCaller->cursorLocation());
    m_textFieldCaller->setCursorLocation(m_textFieldCaller->cursorLocation() + strlen(editedText));
-#if MATRIX_LIST_VARIABLES
+#if MATRIX_VARIABLES
+    m_selectableTableView.deselectTable();
    m_currentPage = Page::RootMenu;
 #endif
    app()->dismissModalViewController();
@@ -78,11 +81,13 @@ bool VariableBoxController::ContentViewController::handleEvent(Ion::Events::Even
 int VariableBoxController::ContentViewController::numberOfRows() {
  switch (m_currentPage) {
    case Page::RootMenu:
-      return 3;
+      return k_numberOfMenuRows;
    case Page::Scalar:
      return GlobalContext::k_maxNumberOfScalarExpressions;
+#if LIST_VARIABLES
    case Page::List:
      return GlobalContext::k_maxNumberOfListExpressions;
+#endif
    case Page::Matrix:
      return GlobalContext::k_maxNumberOfMatrixExpressions;
    default:
@@ -130,16 +135,17 @@ void VariableBoxController::ContentViewController::willDisplayCellForIndex(Highl
  }
  myCell->displayExpression(true);
  if (expression) {
-    /* TODO: implement matrix and list contexts */
-    //myCell->setExpression(expression->createLayout());
-  // TODO: display the dimensgion of the list/matrice as subtitle
-    /* char buffer[4];
-     * buffer[0] = (Matrice *)expression->dim(0);
-     * buffer[1] = 'x';
-     * buffer[2] = (Matrice *)expression->dim(1)
-     * buffer[3] = 0;
-     * myCell->setSubtitle(buffer);*/
+    assert(expression->type() == Expression::Type::Matrix);
+    Matrix * m = (Matrix *)expression;
+    /* TODO: implement list contexts */
+    myCell->setExpression((Expression *)expression);
+    char buffer[2*Complex::bufferSizeForFloatsWithPrecision(2)+1];
+    int numberOfChars = Complex::convertFloatToText(m->numberOfRows(), buffer, Complex::bufferSizeForFloatsWithPrecision(2), 2, Expression::FloatDisplayMode::Decimal);
+    buffer[numberOfChars++] = 'x';
+    Complex::convertFloatToText(m->numberOfColumns(), buffer+numberOfChars, Complex::bufferSizeForFloatsWithPrecision(2), 2, Expression::FloatDisplayMode::Decimal);
+    myCell->setSubtitle(buffer);
  } else {
+    myCell->setExpression(nullptr);
    myCell->setSubtitle("Vide");
  }
 }
@@ -153,8 +159,10 @@ KDCoordinate VariableBoxController::ContentViewController::rowHeight(int index)
  }
  const Expression * expression = expressionForIndex(index);
  if (expression) {
-    KDCoordinate expressionHeight = expression->createLayout()->size().height();
-    return expressionHeight;
+    ExpressionLayout * layout = expression->createLayout();
+    KDCoordinate expressionHeight = layout->size().height();
+    delete layout;
+    return expressionHeight+k_leafMargin;
  }
  return k_leafRowHeight;
 }
@@ -189,16 +197,23 @@ const Expression * VariableBoxController::ContentViewController::expressionForIn
    return m_context->expressionForSymbol(&symbol);
  }
  if (m_currentPage == Page::Matrix) {
-    return nullptr;
+    const Symbol symbol = Symbol::matrixSymbol('0'+(char)index);
+    return m_context->expressionForSymbol(&symbol);
  }
+#if LIST_VARIABLES
  if (m_currentPage == Page::List) {
    return nullptr;
  }
+#endif
  return nullptr;
 }

 VariableBoxController::ContentViewController::Page VariableBoxController::ContentViewController::pageAtIndex(int index) {
+#if LIST_VARIABLES
  Page pages[3] = {Page::Scalar, Page::List, Page::Matrix};
+#else
+  Page pages[2] = {Page::Scalar, Page::Matrix};
+#endif
  return pages[index];
 }

@@ -207,11 +222,13 @@ void VariableBoxController::ContentViewController::putLabelAtIndexInBuffer(int i
    buffer[0] = 'A' + index;
    buffer[1] = 0;
  }
+#if LIST_VARIABLES
  if (m_currentPage == Page::List) {
    buffer[0] = 'L';
    buffer[1] = '0' + index;
    buffer[2] = 0;
  }
+#endif
  if (m_currentPage == Page::Matrix) {
    buffer[0] = 'M';
    buffer[1] = '0' + index;
@@ -221,7 +238,11 @@ void VariableBoxController::ContentViewController::putLabelAtIndexInBuffer(int i

 I18n::Message VariableBoxController::ContentViewController::nodeLabelAtIndex(int index) {
  assert(m_currentPage == Page::RootMenu);
+#if LIST_VARIABLES
  I18n::Message labels[3] = {I18n::Message::Number, I18n::Message::List, I18n::Message::Matrix};
+#else
+  I18n::Message labels[2] = {I18n::Message::Number, I18n::Message::Matrix};
+#endif
  return labels[index];
 }

@@ -234,13 +255,18 @@ void VariableBoxController::ContentViewController::reloadData() {
 }

 void VariableBoxController::ContentViewController::resetPage() {
-#if MATRIX_LIST_VARIABLES
+#if MATRIX_VARIABLES
  m_currentPage = Page::RootMenu;
 #else
  m_currentPage = Page::Scalar;
 #endif
 }

+void VariableBoxController::ContentViewController::viewDidDisappear() {
+  m_selectableTableView.deselectTable();
+  ViewController::viewDidDisappear();
+}
+
 VariableBoxController::VariableBoxController(Context * context) :
  StackViewController(nullptr, &m_contentViewController, true, KDColorWhite, Palette::PurpleBright, Palette::PurpleDark),
  m_contentViewController(this, context)
--- a/apps/variable_box_controller.h
+++ b/apps/variable_box_controller.h
@@ -1,6 +1,8 @@
 #ifndef APPS_VARIABLE_BOX_CONTROLLER_H
 #define APPS_VARIABLE_BOX_CONTROLLER_H

+#define MATRIX_VARIABLES 1
+
 #include <escher.h>
 #include <poincare.h>
 #include "variable_box_leaf_cell.h"
@@ -32,16 +34,24 @@ private:
    void setTextFieldCaller(TextField * textField);
    void reloadData();
    void resetPage();
+    void viewDidDisappear() override;
  private:
    enum class Page {
      RootMenu,
      Scalar,
+#if LIST_VARIABLES
      List,
+#endif
      Matrix
    };
    constexpr static int k_maxNumberOfDisplayedRows = 6; //240/40
-    constexpr static int k_numberOfMenuRows = 3; //240/40
+#if LIST_VARIABLES
+    constexpr static int k_numberOfMenuRows = 3;
+#else
+    constexpr static int k_numberOfMenuRows = 2;
+#endif
    constexpr static KDCoordinate k_leafRowHeight = 40;
+    constexpr static KDCoordinate k_leafMargin = 10;
    constexpr static KDCoordinate k_nodeRowHeight = 40;
    Page pageAtIndex(int index);
    void putLabelAtIndexInBuffer(int index, char * buffer);
--- a/apps/variable_box_leaf_cell.cpp
+++ b/apps/variable_box_leaf_cell.cpp
@@ -5,12 +5,20 @@ using namespace Poincare;

 VariableBoxLeafCell::VariableBoxLeafCell() :
  HighlightCell(),
+  m_expressionLayout(nullptr),
  m_labelView(KDText::FontSize::Small, 0, 0.5, KDColorBlack, KDColorWhite),
  m_subtitleView(KDText::FontSize::Small, 0, 0.5, Palette::GreyDark, KDColorWhite),
+  m_expressionView(1.0f, 0.5f),
  m_displayExpression(false)
 {
 }

+VariableBoxLeafCell::~VariableBoxLeafCell() {
+  if (m_expressionLayout != nullptr) {
+    delete m_expressionLayout;
+    m_expressionLayout = nullptr;
+  }
+}
 void VariableBoxLeafCell::displayExpression(bool displayExpression) {
  m_displayExpression = displayExpression;
 }
@@ -37,10 +45,19 @@ void VariableBoxLeafCell::layoutSubviews() {
  KDCoordinate width = bounds().width();
  KDCoordinate height = bounds().height();
  if (numberOfSubviews() == 3) {
-    m_labelView.setFrame(KDRect(k_separatorThickness+k_widthMargin, k_separatorThickness, width/2-k_separatorThickness-k_widthMargin, height/2 - k_separatorThickness));
-    m_subtitleView.setFrame(KDRect(k_separatorThickness+k_widthMargin, height/2, width/2-k_widthMargin-k_separatorThickness, height/2-k_separatorThickness));
+    KDSize labelSize = m_labelView.minimalSizeForOptimalDisplay();
+    KDSize subtitleSize = m_subtitleView.minimalSizeForOptimalDisplay();
+    m_labelView.setFrame(KDRect(k_separatorThickness+k_widthMargin, k_separatorThickness, labelSize.width(), height/2 - k_separatorThickness));
+    m_subtitleView.setFrame(KDRect(k_separatorThickness+k_widthMargin, height/2, subtitleSize.width(), height/2-k_separatorThickness));
    m_subtitleView.setAlignment(0.0f, 0.5f);
-    m_expressionView.setFrame(KDRect(width/2, k_separatorThickness, width/2-k_separatorThickness-k_widthMargin, height-2*k_separatorThickness));
+    KDCoordinate maxTextSize = subtitleSize.width() > labelSize.width() ? subtitleSize.width() : labelSize.width();
+    KDCoordinate expressionAvailableSize = width-k_separatorThickness-3*k_widthMargin-maxTextSize;
+    m_expressionView.setFrame(KDRect(width - expressionAvailableSize - k_widthMargin, k_separatorThickness, expressionAvailableSize, height-2*k_separatorThickness));
+    if (m_expressionView.minimalSizeForOptimalDisplay().width() > expressionAvailableSize) {
+      m_expressionView.setAlignment(0.0f, 0.5f);
+    } else {
+      m_expressionView.setAlignment(1.0f, 0.5f);
+    }
    return;
  }
  m_labelView.setFrame(KDRect(k_separatorThickness+k_widthMargin, k_separatorThickness, width/2-k_separatorThickness-k_widthMargin, height-2*k_separatorThickness));
@@ -66,8 +83,15 @@ void VariableBoxLeafCell::setSubtitle(const char * text) {
  layoutSubviews();
 }

-void VariableBoxLeafCell::setExpression(ExpressionLayout * expressionLayout) {
-  m_expressionView.setExpression(expressionLayout);
+void VariableBoxLeafCell::setExpression(Expression * expression) {
+  if(m_expressionLayout != nullptr) {
+    delete m_expressionLayout;
+    m_expressionLayout = nullptr;
+  }
+  if (expression) {
+    m_expressionLayout = expression->createLayout();
+  }
+  m_expressionView.setExpression(m_expressionLayout);
 }

 void VariableBoxLeafCell::drawRect(KDContext * ctx, KDRect rect) const {
--- a/apps/variable_box_leaf_cell.h
+++ b/apps/variable_box_leaf_cell.h
@@ -2,15 +2,17 @@
 #define APPS_VARIABLE_BOX_LEAF_CELL_H

 #include <escher.h>
+#include <poincare.h>

 class VariableBoxLeafCell : public HighlightCell {
 public:
  VariableBoxLeafCell();
+  ~VariableBoxLeafCell();
  void displayExpression(bool displayExpression);
  void reloadCell() override;
  void setLabel(const char * text);
  void setSubtitle(const char * text);
-  void setExpression(Poincare::ExpressionLayout * expressionLayout);
+  void setExpression(Poincare::Expression * expression);
  void drawRect(KDContext * ctx, KDRect rect) const override;
 private:
  constexpr static KDCoordinate k_separatorThickness = 1;
@@ -18,6 +20,9 @@ private:
  int numberOfSubviews() const override;
  View * subviewAtIndex(int index) override;
  void layoutSubviews() override;
+  /* The cell is responsible to delete the layout that may be created by its
+   * dynamic method 'setExpression'.*/
+  Poincare::ExpressionLayout * m_expressionLayout;
  BufferTextView m_labelView;
  BufferTextView m_subtitleView;
  ExpressionView m_expressionView;
--- a/poincare/include/poincare/global_context.h
+++ b/poincare/include/poincare/global_context.h
@@ -29,6 +29,7 @@ public:
 private:
  int symbolIndex(const Symbol * symbol) const;
  Expression * m_expressions[k_maxNumberOfScalarExpressions];
+  Expression * m_matrixExpressions[k_maxNumberOfMatrixExpressions];
  Complex m_pi;
  Complex m_e;
 };
--- a/poincare/include/poincare/symbol.h
+++ b/poincare/include/poincare/symbol.h
@@ -8,19 +8,33 @@ namespace Poincare {
 class Symbol : public LeafExpression {
 public:
  enum SpecialSymbols : char {
-    Ans = '^',
-    un = 1,
-    un1 = 2,
-    vn = 3,
-    vn1 = 4,
-    wn = 5,
-    wn1 = 6
+    /* We can use characters from 1 to 31 as they do not correspond to usual
+     * characters but events as 'end of text', 'backspace'... */
+    Ans = 1,
+    un = 2,
+    un1 = 3,
+    vn = 4,
+    vn1 = 5,
+    wn = 6,
+    wn1 = 7,
+    M0 = 8,
+    M1 = 9,
+    M2,
+    M3,
+    M4,
+    M5,
+    M6,
+    M7,
+    M8,
+    M9 = 17
  };
+  static SpecialSymbols matrixSymbol(char index);
  Symbol(char name);
  Type type() const override;
  const char name() const;
  Expression * clone() const override;
  bool valueEquals(const Expression * e) const override;
+  bool isMatrixSymbol() const;
 private:
  float privateApproximate(Context& context, AngleUnit angleUnit) const override;
  Expression * privateEvaluate(Context& context, AngleUnit angleUnit) const override;
--- a/poincare/src/expression_lexer.l
+++ b/poincare/src/expression_lexer.l
@@ -84,6 +84,7 @@ using namespace Poincare;
 [0-9]+ { poincare_expression_yylval.string.address = yytext; poincare_expression_yylval.string.length = yyleng; return DIGITS; }
 [A-Zxn] { poincare_expression_yylval.character = yytext[0]; return SYMBOL; }
 [a-z;:"_=<>] { return UNDEFINED_SYMBOL; }
+M[0-9] { poincare_expression_yylval.character = Symbol::matrixSymbol(yytext[1]); return SYMBOL; }
 u\(n\) { poincare_expression_yylval.character = Symbol::SpecialSymbols::un; return SYMBOL; }
 u\(n\+1\) { poincare_expression_yylval.character = Symbol::SpecialSymbols::un1; return SYMBOL; }
 v\(n\) { poincare_expression_yylval.character = Symbol::SpecialSymbols::vn; return SYMBOL; }
--- a/poincare/src/global_context.cpp
+++ b/poincare/src/global_context.cpp
@@ -1,4 +1,5 @@
 #include <poincare/global_context.h>
+#include <poincare/matrix.h>
 #include <assert.h>
 #include <math.h>
 #include <ion.h>
@@ -12,6 +13,9 @@ GlobalContext::GlobalContext() :
  for (int i = 0; i < k_maxNumberOfScalarExpressions; i++) {
    m_expressions[i] = nullptr;
  }
+  for (int i = 0; i < k_maxNumberOfMatrixExpressions ; i++) {
+    m_matrixExpressions[i] = nullptr;
+  }
 }

 GlobalContext::~GlobalContext() {
@@ -21,6 +25,12 @@ GlobalContext::~GlobalContext() {
    }
    m_expressions[i] = nullptr;
  }
+  for (int i = 0; i < k_maxNumberOfMatrixExpressions; i++) {
+    if (m_matrixExpressions[i] != nullptr) {
+      delete m_matrixExpressions[i];
+    }
+    m_matrixExpressions[i] = nullptr;
+  }
 }

 Complex * GlobalContext::defaultExpression() {
@@ -40,6 +50,10 @@ const Expression * GlobalContext::expressionForSymbol(const Symbol * symbol) {
  if (symbol->name() == Ion::Charset::Exponential) {
    return &m_e;
  }
+  if (symbol->isMatrixSymbol()) {
+    int indexMatrix = symbol->name() - (char)Symbol::SpecialSymbols::M0;
+    return m_matrixExpressions[indexMatrix];
+  }
  int index = symbolIndex(symbol);
  if (index < 0 || index >= k_maxNumberOfScalarExpressions) {
    return nullptr;
@@ -51,6 +65,18 @@ const Expression * GlobalContext::expressionForSymbol(const Symbol * symbol) {
 }

 void GlobalContext::setExpressionForSymbolName(Expression * expression, const Symbol * symbol) {
+  if (symbol->isMatrixSymbol()) {
+    int indexMatrix = symbol->name() - (char)Symbol::SpecialSymbols::M0;
+    assert(indexMatrix >= 0 && indexMatrix < k_maxNumberOfMatrixExpressions);
+    if (m_expressions[indexMatrix] != nullptr) {
+      delete m_matrixExpressions[indexMatrix];
+      m_matrixExpressions[indexMatrix] = nullptr;
+    }
+    if (expression->type() == Expression::Type::Matrix) {
+      m_matrixExpressions[indexMatrix] = expression->clone();
+    }
+    return;
+  }
  int index = symbolIndex(symbol);
  if (index < 0 || index >= k_maxNumberOfScalarExpressions) {
    return;
--- a/poincare/src/symbol.cpp
+++ b/poincare/src/symbol.cpp
@@ -10,6 +10,34 @@ extern "C" {

 namespace Poincare {

+Symbol::SpecialSymbols Symbol::matrixSymbol(char index) {
+  switch (index - '0') {
+    case 0:
+      return SpecialSymbols::M0;
+    case 1:
+      return SpecialSymbols::M1;
+    case 2:
+      return SpecialSymbols::M2;
+    case 3:
+      return SpecialSymbols::M3;
+    case 4:
+      return SpecialSymbols::M4;
+    case 5:
+      return SpecialSymbols::M5;
+    case 6:
+      return SpecialSymbols::M6;
+    case 7:
+      return SpecialSymbols::M7;
+    case 8:
+      return SpecialSymbols::M8;
+    case 9:
+      return SpecialSymbols::M9;
+    default:
+      assert(false);
+      return SpecialSymbols::M0;
+  }
+}
+
 Symbol::Symbol(char name) :
  m_name(name)
 {
@@ -64,6 +92,11 @@ ExpressionLayout * Symbol::privateCreateLayout(FloatDisplayMode floatDisplayMode
  if (m_name == SpecialSymbols::wn1) {
    return new BaselineRelativeLayout(new StringLayout("w", 1), new StringLayout("n+1",3, KDText::FontSize::Small), BaselineRelativeLayout::Type::Subscript);
  }
+  if (isMatrixSymbol()) {
+    char mi[3] = "M0";
+    mi[1] = m_name-(char)SpecialSymbols::M0+'0';
+    return new StringLayout(mi, 2);
+  }
  return new StringLayout(&m_name, 1);
 }

@@ -76,4 +109,11 @@ bool Symbol::valueEquals(const Expression * e) const {
  return (m_name == ((Symbol *)e)->m_name);
 }

+bool Symbol::isMatrixSymbol() const {
+  if (m_name >= (char)SpecialSymbols::M0 && m_name <= (char)SpecialSymbols::M9) {
+    return true;
+  }
+  return false;
+}
+
 }