I have some analysis code that depends on the node number increases centrifugally. I could write some code to post-process the swc result from V3D, but do you have an easy fix within V3D? The node number initially increases centrifugally when I use V3D to trace the structure. But if I decompose or edit the structure, the node number becomes decreasing centrifugally within a segment and stay this way (i.e. the node order does not reverse back to the original even if I decompose or edit the structure again). Does this suggest the decompose function can be somehow modified to dictate the node number be the same as the original?

As to the difference in speed between the rejoin and decompose function, it is only obvious when dealing with structures with hundreds of branches. I imagine that the decompose function involves breaking the structure into segments at branching points while the rejoin function involves removing redundant branching points (i.e. the ending node of an upstream segment is the beginning node of the corresponding downstream segment). If this is the case, the two functions should be similar in speed. That's why I think the difference in speed might be caused by some inefficiency when the node number is reversed.

Thanks again,
Jichao