/** Parse the expression in m_ExpressionText
* and calculate result.
* Return the result as a double.
* If quiet ist true, no signals will be emitted and m_Expressiontext will not be modified.
* If quiet is false, Log will be updated and m_Expressiontext will be set to the result of the calculation.
* A logTextChanged and an expressionTextChanged signal will be emitted.
*/
double Calculator::parseExpression(bool quiet)
{
QStringList expressionParts = m_ExpressionParts; //work on a copy, keep the original
int partCount = expressionParts.size();
double result = 0.0;
try{
//Parse the expression
while(partCount > 1)
{
parseSubexpression(expressionParts);
partCount = expressionParts.size();
}
if(expressionParts.size() == 0)
throw ExExpressionError(tr("Expression could not be evaluated."));
if( ! quiet)
{
m_ExpressionText = m_ExpressionParts.join("") + ( "= " + expressionParts[0]);
//Log the expression and its result
m_LogText += m_ExpressionText + "\n";
emit logTextChanged(m_LogText);
//replace the expression with its result
m_ExpressionParts.clear();
m_ExpressionParts.append(expressionParts[0]);
m_ExpressionText = expressionParts[0];
emit expressionTextChanged(m_ExpressionText);
result = m_ExpressionText.toDouble();
}
else //keep m_ExpressionParts and m_Expressiontext as they are
{
if(isVariable(expressionParts[0]))
result = getVariableValue(expressionParts[0]);
else result = expressionParts[0].toDouble();
}
}
catch(ExExpressionError & e)
{
qDebug("Calculator::parseExpression caught ExExpressionError: %s", e.what());
if(quiet)
throw e;
else emit errorMessage(tr("Error"), e.what());
}
catch(std::exception &e)
{
qDebug("Calculator::parseExpression caught std::exception: %s", e.what());
if(quiet)
throw e;
else emit errorMessage(tr("Error"), e.what());
}
catch(...)
{
qDebug("Calculator::parseExpression caught unknown exception.");
if(quiet)
throw std::exception();
else emit errorMessage(tr("Error"),"Calculator::parseExpression caught unknown exception.");
}
return result;
}
void FilterExpressionsPreferencesFrame::on_expressionTreeWidget_itemActivated(QTreeWidgetItem *item, int column)
{
if (!item || cur_line_edit_) return;
QWidget *editor = NULL;
cur_column_ = column;
switch (column) {
case label_col_:
{
cur_line_edit_ = new QLineEdit();
cur_column_ = column;
saved_col_string_ = item->text(label_col_);
connect(cur_line_edit_, SIGNAL(editingFinished()), this, SLOT(labelEditingFinished()));
editor = cur_line_edit_;
break;
}
case expression_col_:
{
SyntaxLineEdit *syntax_edit = new SyntaxLineEdit();
saved_col_string_ = item->text(expression_col_);
connect(syntax_edit, SIGNAL(textChanged(QString)),
this, SLOT(expressionTextChanged(QString)));
connect(syntax_edit, SIGNAL(editingFinished()), this, SLOT(expressionEditingFinished()));
editor = cur_line_edit_ = syntax_edit;
break;
}
default:
return;
}
if (cur_line_edit_) {
cur_line_edit_->setText(saved_col_string_);
cur_line_edit_->selectAll();
connect(cur_line_edit_, SIGNAL(destroyed()), this, SLOT(lineEditDestroyed()));
}
if (editor) {
QFrame *edit_frame = new QFrame();
QHBoxLayout *hb = new QHBoxLayout();
QSpacerItem *spacer = new QSpacerItem(5, 10);
hb->addWidget(editor, 0);
hb->addSpacerItem(spacer);
hb->setStretch(1, 1);
hb->setContentsMargins(0, 0, 0, 0);
edit_frame->setLineWidth(0);
edit_frame->setFrameStyle(QFrame::NoFrame);
// The documentation suggests setting autoFillbackground. That looks silly
// so we clear the item text instead.
item->setText(cur_column_, "");
edit_frame->setLayout(hb);
ui->expressionTreeWidget->setItemWidget(item, cur_column_, edit_frame);
editor->setFocus();
}
}
/** Deletes expresssion text. Deletes Log, when expression is empty.
*/
void Calculator::clearAll()
{
if(m_ExpressionText.isEmpty())
{
m_LogText = "";
emit logTextChanged(m_LogText);
}
m_ExpressionParts.clear();
m_ExpressionText = "";
emit expressionTextChanged(m_ExpressionText);
}
/** Deletes last character.
*/
void Calculator::clearLast()
{
if(m_ExpressionParts.size() == 0)
return;
m_ExpressionParts.removeLast();
if(m_ExpressionParts.size() > 0 && isFunction(m_ExpressionParts.last())) //remove ( and function name
m_ExpressionParts.removeLast();
m_ExpressionText = m_ExpressionParts.join("");
emit expressionTextChanged(m_ExpressionText);
}
Calculator::Calculator(QObject *parent) :
QObject(parent)
{
m_NextAngleMode = m_TextRad;
m_AngleMode = m_TextDeg;
m_x = 0.0;
//whatever it may be good for. Does not affect GUI, if GUI is not yet ready
emit logTextChanged(m_LogText);
emit expressionTextChanged(m_ExpressionText);
emit angleModeChanged(m_AngleMode, m_NextAngleMode);
connect(&plotter, SIGNAL(plotSetupChanged(QString)),
this, SLOT(slot_Plotter_plotSetupChanged(QString)));
connect(&plotter, SIGNAL(yValueRequest(double,double*)),
this, SLOT(slot_Plotter_yValueRequest(double,double*)));
}
/** Append text to Expression. Overwrites a trailing operator with the new one, if a sequence of
* two operators is input.
* Recognizes and executes C, AC and = commands.
*/
void Calculator::addToExpressionText(const QString & buttonText)
{
QString text = buttonText;
try{
if(text == "C")
clearLast();
else if(text == "AC")
clearAll();
else if(text == "+/-")
changeSign();
else if(text == m_TextRad)
setAngleMode(text);
else if(text == m_TextDeg)
setAngleMode(text);
else if(text == "=")
{
if(isPlotExpression())
createPlot();
else parseExpression();
}
else if(text=="x")
addVariable(text);
else if(text.startsWith("Plot"))
plotter.processPlotCommand(text);
else{ //we have a digit, operator or function
//no clear or evaluate command
if(text == "x^y") //convert to operator
text = "^";
if(isNumber(text)){ //No parenthesis, we have a digit or a decimal separator
addDigit(text);
emit guiStateSuggested(STATE_STANDARD); //return to std page, if on Fn Page for entering E
}
else if(isOperator(text)) //operator or digit
{
addOperator(text);
}
else if(isParenthesis(text)) //we have a parenthesis
{
addParenthesis(text);
}
else if(isFunction(text)) //we have a function
{
addFunctionCall(text);
}
else if(isVariable(text)) //we have a variable
{
addVariable(text);
}
else throw ExExpressionError(tr("Unknown command:") + text);
} //end digit operator or function
m_ExpressionText = m_ExpressionParts.join("");
if(isPlotExpression())
emit expressionTextChanged("y=" + m_ExpressionText);
else emit expressionTextChanged(m_ExpressionText);
} //end try
catch(ExExpressionError e)
{
emit guiStateSuggested(STATE_STANDARD);
emit errorMessage(tr("Input Error"),e.what());
}
catch(std::exception e)
{
emit guiStateSuggested(STATE_STANDARD);
emit errorMessage(tr("Unknown Input Error"),e.what());
}
}
