get a row number of where to place each clone label.
get_clone_id_label_positions.Rd
A single clone can appear on multiple clades of the tree or in one monophyletic group. On the heatmap, we need to determine were to put a clone ID label (e.g., A, B, C, etc), as we don't want a label for each cell id. Typically, we label the largest clade with the clone ID, and then provide a legend mapping clone colors to IDs. This function will find the "middle" cell ID of the clade being labelled as the position to place the clone ID.