Compute the longest path (aka spine or backbone) of a neuron

spine(n, UseStartPoint = FALSE, SpatialWeights = TRUE, invert = FALSE,
  rval = c("neuron", "length", "ids"))

Arguments

n

the neuron to consider.

UseStartPoint

Whether to use the StartPoint of the neuron (often the soma) as the starting point of the returned spine.

SpatialWeights

logical indicating whether spatial distances (default) should be used to weight segments instead of weighting each edge equally.

invert

When invert=TRUE the spine is pruned away instead of being selected. This is only valid when rval='neuron' or rval='ids'.

rval

Character vector indicating the return type, one of 'neuron', 'length' or 'ids'. See Value section.

Value

Either

  • a neuron object corresponding to the longest path or

  • the length of the longest path (when rval="length") or

  • an integer vector of raw point indices (when rval="ids").

See also

diameter, shortest.paths, prune_strahler for removing lower order branches from a neuron, prune for removing parts of a neuron by spatial criteria.

Other neuron: neuron, ngraph, plot.dotprops, potential_synapses, prune, resample, rootpoints, subset.neuron

Examples

pn.spine=spine(Cell07PNs[[1]])
plot3d(Cell07PNs[[1]]) plot3d(pn.spine, lwd=4, col='black')
# just extract length spine(Cell07PNs[[1]], rval='length')
#> [1] 186.0859
# same result since StartPoint is included in longest path spine(Cell07PNs[[1]], rval='length', UseStartPoint=TRUE)
#> [1] 186.0859
# extract everything but the spine antispine=spine(Cell07PNs[[1]], invert=TRUE)
plot3d(Cell07PNs[[1]]) plot3d(antispine, lwd=4, col='red')