Uploaded image for project: 'The Virtual Brain'
  1. The Virtual Brain
  2. TVB-1124

Connectivity - Space-time plot should display weight=0 as black

    XMLWordPrintable

    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Critical
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 1.1.1
    • Component/s: None
    • Labels:
      None

      Description

      Paula:
      The entries of the weight s connectivity matrix whose values are zero entries
      shouldn't be displayed, or better said, they should be in black, and not in
      white-ish as it is currently done.

      Lia:
      currently we make a distinction between a connection with weight 0 and a connection not activated at all
      this means that in the overall matrix, we have a replica of the grid-matrix on the right-side of the cockpit,
      while in the specific slices selected, the connections which get activated (due to tract-length) are displayed with some color
      (including white, when the connection-weight is 0) compared with black, which means the current delay does not affect at all a connection
      As I am thinking on this.... maybe the 0 connections are not correct.... but I can not judge.
      If you think we do not need to make the distinction I mentioned above, surely, we can display every 0 as black... but right now, that white shows some info....

      Paula:
      I guessed that much. The space-time structure is mainly to visualize the non-
      zero entries in the weights matrix with respect to the time-delay interval
      they belong to (given by the tract lengths matrix and conduction speed). Zero
      entries in the weights matrix with non-zero entries in the tract-lengths is
      mainly an artifact due to the nature of the demonstration datatset, that is, a
      hand made dataset that brings together data from the primate brain (weights)
      and DTI/DSI data from a human (tract-lengths). In principle, in a dataset
      derived from one subject, weights in the connectivity matrix reflect a
      property of the connections, therefore if there is no connection, the weight
      will be zero and distance will be ... well, it could be anything that the
      tractography algorithm decides. So, zero weights mean that those connections
      don't count. So, their distances don't count at all. Let's say that we could
      set the distance to zero. Why 0? Well, it could be set to infinity, or to a
      non-numerical value, however this would bring problems into the simulator
      because the history array will have to be of size infinity along the time
      axis...

        Gliffy Diagrams

          Attachments

            Activity

              People

              Assignee:
              mihai.andrei Mihai Andrei
              Reporter:
              paula.sanz-leon Paula Sanz Leon
              Votes:
              0 Vote for this issue
              Watchers:
              1 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved:

                  Time Tracking

                  Estimated:
                  Original Estimate - 4 hours
                  4h
                  Remaining:
                  Remaining Estimate - 0 minutes
                  0m
                  Logged:
                  Time Spent - 3 hours Time Not Required
                  3h