6 .Nd Visualize quivers on console
11 is a text-based program to interact with quivers. It is intended to be
12 used in situations where
14 is unusable, and where by-hand computation is inconvenient.
18 starts, it shows a sample quiver, which does not have many interesting
21 Vertices are displayed in a vertical list. The left-hand column displays
22 the index of the vertex, the right displays the name.
24 interacts with vertices by index for compactness' sake.
26 Edges are displayed by weight in a matrix. The entry of row i, column
27 j is edge weight ε_{ij} of the quiver
28 .Pq a blank entry represents 0 .
30 The quiver is controlled by primitive text commands. No tab
31 completion/history is implemented. Help is available by typing
34 The following commands are available. To cancel an action when input is
40 Display the quiver, as described in
43 Mutate the quiver at the vertex with index
46 Delete the vertex with index
48 .It delete Ar idx-one idx-two
49 Delete edges between vertices with indices
53 The order of the two parameters is unimportant.
55 Create a new vertex, called
57 .It edge Ar i Ar j Ar p / Ar q
62 The weights of both directions of the edge will be modifed by the
73 .Dl ε_{ij} := ε_{ij} + (p · F_j) / (q · GCD(F_i, F_j))
74 .Dl ε_{ji} := ε_{ij} - (p · F_i) / (q · GCD(F_i, F_j))
79 are the fatnesses of the vertices with indices
87 is permitted; it implies using
92 Increment the fatness of the vertex at index
96 Decrement the fatness of the vertex at index
100 Save the current quiver to
102 The file will be readable by
107 .Pq discarding the current quiver .
108 The file may have been written by
112 Example quivers may have been installed along with this program,
114 .Pa /usr/share/clav/ .
119 Edge weights are, for performance reasons
121 .Xr clav-mutation-find 1
122 .Pc , stored as fractions with
123 numerator and denominator in system-dependent ranges. While it probably
124 will not be an issue for
126 usage, causing edge weights to increase arbitrarily will eventually cause
128 to compute an unrepresentable edge weight. In this situation,
130 will terminate with a diagnostic message rather than display incorrect
139 is not graphical, there will be no good x/y information associated with
140 any vertices created by
142 This will probably be confusing until the quiver is rarranged by a user.
144 .An S. Gilles Aq Mt sgilles@math.umd.edu