Compute the longest path (aka spine or backbone) of a neuron
spine(
n,
UseStartPoint = FALSE,
SpatialWeights = TRUE,
invert = FALSE,
rval = c("neuron", "length", "ids")
)
the neuron to consider.
Whether to use the StartPoint of the neuron (often the soma) as the starting point of the returned spine.
logical indicating whether spatial distances (default) should be used to weight segments instead of weighting each edge equally.
When invert=TRUE
the spine is pruned away instead of
being selected. This is only valid when rval='neuron'
or
rval='ids'
.
Character vector indicating the return type, one of
'neuron'
, 'length'
or 'ids'
. See Value section.
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"
).
Note that when UseStartPoint=FALSE
, spine
will find
the path between all end points (including the root if it is an end point).
Since the longest path must include an end point, this is equivalent to
searching the whole graph for the longest path, but considerably faster.
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()
pn.spine=spine(Cell07PNs[[1]])
# \donttest{
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)
# \donttest{
plot3d(Cell07PNs[[1]])
plot3d(antispine, lwd=4, col='red')
# }