# Connectome matrix

Hi mrtrix user,
Each entry of the diagonal of the connectome matrix implies what? Is it the number of streamlines connected between the same region?

regards,
Souvik

Welcome @Souvik_Mitra!

Yes, this will be the number of streamlines (or any other connectome edge metric calculation) corresponding to those streamlines for which both ends are assigned to the same parcel. While these data are typically ignored in graph theory analyses (and can be immediately zeroed by using the `-zero_diagonal` option in `tck2connectome`), they are nevertheless present in the data, and so are included by default.

Rob

Thank you for the help