/// <summary>
/// Sets a new expression for the plot line
/// </summary>
/// <param name="source">The data source</param>
/// <param name="expression">The new expression to set</param>
public void SetExpression(DataChart source, string expression)
{
this.Expression = expression;
if (!string.IsNullOrEmpty(expression))
{
// Attempt to generate the data table for the given expression
this.GetValue = source.getExpressionEvaluator(expression);
Generate(source);
}
if (ExpressionChanged != null)
{
ExpressionChanged(this);
}
}
/// <summary>
/// Generates the data to use in the plot line
/// </summary>
/// <param name="source"></param>
public void Generate(DataChart source)
{
if (!DataMutex.WaitOne(250))
{
return;
}
List <string> symbols = source.GetSymbolList(Symbol);
this.Data = new DataTable();
foreach (var s in symbols)
{
List <StockDataInterface> sources;
if (this.GetValue == null)
{
this.GetValue = source.getExpressionEvaluator(Expression); // Create the expression only when needed to speed up the GUI and allow parallel compiling
}
if (!source.getDataList(s, out sources) || (GetValue == null))
{
break;
}
// Load the sources first (need to load to the end before accessing the data since loading later sources could backfill data) */
for (int i = 0; i < sources.Count; i++)
{
sources[i].Load(source.Session);
}
// Ensure columns are added for the data types
if (Data.Columns.Count < 2)
{
Data.Columns.Add(source.XAxis, source.XAxisGetValue(sources[0], 0).GetType());
Data.Columns.Add(Expression, GetValue(sources[0], 0).GetType());
}
// Create a table of each data point in the specified range
for (int i = 0; i < sources.Count; i++)
{
string symbol;
DateTime start;
TimeSpan interval;
sources[i].GetInfo(out symbol, out start, out interval);
if (start >= source.Start)
{
// Add the data set to the table
for (int j = 0; j < sources[i].GetCount(); j++)
{
if (start.AddSeconds(interval.TotalSeconds * j) <= source.End)
{
// Add the point to the table
Data.Rows.Add(source.XAxisGetValue(sources[i], j), GetValue(sources[i], j));
}
else
{
break;
}
}
}
}
}
// Update the line plot data
CreatePlotLine(source);
if (Plot != null)
{
Plot.SetData(Data);
}
DataMutex.ReleaseMutex();
}