private double getFx(string expr)
{
//if (expr.StartsWith("log(-") || expr.StartsWith("log((-") || expr.StartsWith("sqrt(-") || expr.StartsWith("sqrt((-"))
//{
// throw new ArithmeticException("Not Real Expression");
//}
return((UpperY - ParseExpression.parse(expr)) * UnitHeight);
}
private void showTracingInfo(Point point, Line line)
{
tracingInfoBox.Children.Clear();
GraphCanvas.Children.Remove(tracingInfoBox);
tracingInfoBox.Orientation = Orientation.Vertical;
tracingInfoBox.Margin = new Thickness(0, 0, 0, 0);
tracingInfoBox.Background = Brushes.White;
string expr = "";
foreach (var child in FunctionList.Items)
{
StackPanel stackPanel = (StackPanel)(child);
Label exprLabel = stackPanel.Children.OfType <Label>().ElementAt(1);
if (exprLabel.Foreground == line.Stroke)
{
expr = exprLabel.Content.ToString();
break;
}
}
Label funcLabel = new Label();
funcLabel.Content = expr;
Label xLabel = new Label();
xLabel.Content = "X: " + (graphPlotter.LowerX + (point.X / graphPlotter.UnitWidth));
Label yLabel = new Label();
try
{
yLabel.Content = "Y: " + Math.Round(ParseExpression.parse(ParseExpression.replaceVariable(expr,
"(" + Convert.ToString(Math.Round((graphPlotter.LowerX + (point.X / graphPlotter.UnitWidth)), 3)) + ")")), 2);
}
catch (Exception e)
{
Trace.WriteLine(e.Message);
}
tracingInfoBox.Children.Add(funcLabel);
tracingInfoBox.Children.Add(xLabel);
tracingInfoBox.Children.Add(yLabel);
GraphCanvas.Children.Add(tracingInfoBox);
}
private List <Point> getPointsFromExpression(string variableExpr)
{
List <Point> points = new List <Point>();
string expr;
for (double x = 0; x <= GraphCanvas.Width; x += steps)
{
double num = LowerX + (x / UnitWidth);
expr = ParseExpression.replaceVariable(variableExpr, "(" + Convert.ToString(Math.Round(num, 3)) + ")");
try
{
double y = getFx(expr);
if (y < 0)
{
y = 0;
}
if (y > GraphCanvas.Height)
{
y = GraphCanvas.Height;
}
points.Add(new Point(x, y));
//Trace.WriteLine(num + " " + Convert.ToDouble(parser.Parse(expr)) + "\n");
}
catch (Exception e)
{
if (e.Message == "Not Real Expression")
{
if (x < OriginX)
{
x = OriginX;
}
else
{
x = GraphCanvas.Width;
}
}
Trace.WriteLine(num + e.Message);
}
}
return(points);
}
private void addBtn_Click(object sender, RoutedEventArgs e)
{
try
{
string expr = ParseExpression.replaceVariable(inputTB.Text, "(0)");
ParseExpression.parse(expr);
addExpressionToList();
}
catch (Exception exception)
{
if (exception.Message.StartsWith("Value was either too large") ||
exception.Message.StartsWith("Attempted to divide by zero"))
{
addExpressionToList();
}
else
{
MessageBox.Show(invalidFunctionErrorMessage + exception.Message);
}
}
}