Working with generic lists

[Shansen]

All,

A plea for your programming knowledge...

Lst<int> = a single-dimensional list (generic class)

{1,2,3,4}

MDLst<double> = a multi-dimensional list (generic class) where the first sub-element of each element corresponds to the elements of Lst. The first sub-element is a whole number (i.e. integer) but subsequent elements require doubles. (Apologies, if my vernacular is not correct)

{1,x,x,x}
{2,x,x,x}
{3,x,x,x}
{4,x,x,x}

As new elements are added to Lst, or existing elements are removed from Lst, how would you go about implementing the same changes in MDLst?

I imagine it would be something along the lines of (though the syntax escapes me):

if Lst element does not exist in MDLst, then add new element to MDLst (i.e. new {y,x,x,x])
if MDLst element no longer exists in Lst, then remove offending element from MDLst.

As always, thanks and regards
Shannon

[NinjaTrader_Austin]

Shannon, sounds like you will have to create some sort of synchronization method to keep your lists all up to date.

[Shansen]

Austin,

Thanks for the quick reply.

My programming knowledge is not sufficiently advanced to apply the synchronization method. I've implemented the below code (where MDLstAddition & MDLstRemoval = List<int> and Required = Boolean):

      // Mark and add MDLst elements
      MDLstAddition.Clear();
      for (int i = 0; i < Lst.Count; i++) 
      {
        Required = true;
        double LstTest = Convert.ToDouble(Lst[i]);
        for (int j = 0; j < MDLst.Count; j++) 
        {
          if (LstTest == MDLst[j][0])
            Required = false;
        }
        if (Required) 
          MDLstAddition.Add(i);
      }
      for (int i = 0; i < MDLstAddition.Count; i++) 
        MDLst.Insert(0, new List<double>(new double[]{Lst[MDLstAddition[i]],0,0,0,0}));
    
      // Mark and remove MDLst elements      
      MDLstRemoval.Clear();
      for (int i = 0; i < MDLst.Count; i++) 
      {
        if (!(Lst.Contains(Convert.ToInt32(MDLst[i][0]))))
          MDLstRemoval.Add(i);
      }
      for (int i = MDLstRemoval.Count; i > 0; i--) 
        MDLst.RemoveAt(MDLstRemoval[i-1]);

Comments are welcome.
Regards
Shannon

[NinjaTrader_Bertrand]

Shannon, unfortunately I would not be aware of a readymade method for this scenrio, however you can look into ArrayList.Synchronize - http://msdn.microsoft.com/en-us/library/3azh197k.aspx (though I believe it only 'locks' a list to ensure nonconcurrent access).