2 .Dt CLUSTER-ALGEBRA-VISUALIZE 1
5 .Nm cluster-algebra-visualize
6 .Nd displays, and allows mutation of, cluster algebras in an ncurses display
21 may be visualized as a collection of vertices and arrows between the
22 vertices. The arrows have direction and multiplicity, and there cannot
23 be two different arrows between the same two vertices
24 .Pq even if the arrows are reversed .
26 Cluster algebras come with an operation called
28 To mutate a quiver at a particular vertex
36 which both have arrows
53 then add a new arrow from
57 with multiplicity as the product of the multiplicities of
61 .Pq if an arrow is already present, just add to its multiplicity .
62 Once this has been done for all possible pairs (
65 ), reverse the multiplicity
66 .Pq reverse the direction
67 of all arrows touching
70 This operation is rather tedious when the arrows become numerous, so
76 which will show a blank screen. Press
78 to create a new point: move by using h/j/k/l or the arrow keys, pressing
80 to select that position. If you wish to create a shape which is larger
81 than the display allows, use h/j/k/l to scroll the viewport. Add
82 arrows between points by pressing
84 and entering the numbers of points. Pressing
86 and providing a filename will save the current state to that file, and
89 later with that filename as the
91 argument will load the state where you left off.
93 Perform mutation by pressing
95 and entering a list of
96 .Pq whitespace-separated
97 point-names. Mutation will be performed at each of the points in
98 order. For example, running
100 .D1 % cluster-algebra-visualize /usr/share/cluster-algebra-visualize/7_a.txt
103 .Pq depending on where your installation has put various files
104 display the quiver given by Fock and Goncharov when considering the
105 representation of a hyperbolic 3-simplex into SL(7, C). Performing the
106 following sequence of mutations:
109 .D1 m 11 5 1 9 19 23 f 3 b 1b
110 .D1 m 12 6 8 18 4 0 2 a 22 e c 1c
111 .D1 m 13 7 17 5 1 9 f 3 b 21 d 1d
112 .D1 m 14 16 6 8 0 2 e c 20 1e
115 will transform the quiver into the one given by running
117 .D1 % cluster-algebra-visualize /usr/share/cluster-algebra-visualize/7_b.txt
123 .%B Lecture Notes on Cluster Algebras
130 .%A Alexander Goncharov
132 .%T Moduli Spaces of Local Systems and Higher Teichmüller Theory
133 .%J Publications Mathématiques de l’Institut des Hautes Études Scientifiques 103
136 .%O DOI 10.1007/s10240-006-0039-4. Preprint at http://arxiv.org/abs/math/0311149v4
141 No good error handling
143 The display is a haphazard mixture of Unicode and ASCII. The author
144 would have preferred to use Unicode's drawing characters completely,
145 but found too many spacing errors in popular fonts to proceed.
147 Arrows with multiplicities greater than 1 are simply drawn in reverse
148 color. It is not easy to see what their multiplicity actually is,
149 other than saving the quiver state and counting the number of times
150 the arrow appears in the output.
152 Arrows which overlap other arrows are not necessarily drawn
153 intelligently. If vertices are placed close together, the quiver may
156 To delete an arrow, add an arrow going the other way.