first steps

exploration of a tree

adapted from
PLoS supp. material by Hermann Cuntz

← starting_with_trees
→ visual_exploration

The tree was appended to the cell array trees:

>> trees

[1x1 struct]

as a structure with the following organization:

>> trees{1}

ans =

dA: [15x15 double]
X: [15x1 double]
Y: [15x1 double]
Z: [15x1 double]
R: [15x1 double]
D: [15x1 double]
rnames: {'1' 'dendrite'}
Ri: 100
Gm: 5.0000e-004
Cm: 1
name: 'tree1'

>> trees{1}.dA

ans =

(2,1)......1
(3,2)......1
(4,3)......1
(10,3).....1
(5,4)......1
(6,5)......1
(7,6)......1
(9,6)......1
(8,7)......1
(11,10)....1
(15,10)....1
(12,11)....1
(13,12)....1
(14,12)....1

>> trees{1}.D

ans =

4.2506
3.4969
2.8540
2.4839
2.0405
1.6907
1.6019
1.3737
1.2672
2.2141
1.9202
1.6343
1.3279
1.4731
1.2903

It contains the NxN adjacency matrix dA in sparse form which describes the edges between the N nodes of the graph. A few Nx1 vectors attribute individual values to all nodes (e.g. X, Y, Z coordinates; R region index; D diameter values). A cell array of strings rnames attributes a name to each region. A few single values describe homogenously distributed features, here the passive electrotonic parameters. A string name attributes a name to the given tree.