graphviz: circular layout while preserving node order
I think, the only solution is to use a neato' layout and the pos attribut.
To do what you want, I start by creating a small Ruby script to calculate all nodes positions :
radius = 20
(1..128).each do |i|
x = Math.cos(((Math::PI*2)/128.0)*i.to_f)*radius
y = Math.sin(((Math::PI*2)/128.0)*i.to_f)*radius
puts " #{i}[label=\"#{i}\", pos=\"#{x},#{y}!\", shape = \"square\"];"
end
Then, I put the result in the graphviz script :
digraph G {
layout="neato"
1[label="1", pos="19.9759091241034,0.98135348654836!", shape = "square"];
2[label="2", pos="19.9036945334439,1.96034280659121!", shape = "square"];
3[label="3", pos="19.7835301992956,2.93460948910723!", shape = "square"];
4[label="4", pos="19.6157056080646,3.90180644032256!", shape = "square"];
5[label="5", pos="19.4006250638909,4.85960359806528!", shape = "square"];
6[label="6", pos="19.1388067146442,5.80569354508925!", shape = "square"];
7[label="7", pos="18.8308813036604,6.7377970678444!", shape = "square"];
8[label="8", pos="18.4775906502257,7.6536686473018!", shape = "square"];
9[label="9", pos="18.0797858624689,8.55110186860564!", shape = "square"];
10[label="10", pos="17.6384252869671,9.42793473651995!", shape = "square"];
11[label="11", pos="17.1545722000054,10.2820548838644!", shape = "square"];
12[label="12", pos="16.6293922460509,11.111404660392!", shape = "square"];
13[label="13", pos="16.0641506296129,11.9139860898487!", shape = "square"];
14[label="14", pos="15.4602090672547,12.6878656832729!", shape = "square"];
15[label="15", pos="14.8190225070992,13.4311790969404!", shape = "square"];
16[label="16", pos="14.142135623731,14.1421356237309!", shape = "square"];
17[label="17", pos="13.4311790969404,14.8190225070992!", shape = "square"];
18[label="18", pos="12.6878656832729,15.4602090672547!", shape = "square"];
19[label="19", pos="11.9139860898487,16.0641506296129!", shape = "square"];
20[label="20", pos="11.111404660392,16.6293922460509!", shape = "square"];
21[label="21", pos="10.2820548838644,17.1545722000054!", shape = "square"];
22[label="22", pos="9.42793473651996,17.6384252869671!", shape = "square"];
23[label="23", pos="8.55110186860564,18.0797858624689!", shape = "square"];
24[label="24", pos="7.6536686473018,18.4775906502257!", shape = "square"];
25[label="25", pos="6.7377970678444,18.8308813036604!", shape = "square"];
26[label="26", pos="5.80569354508925,19.1388067146442!", shape = "square"];
27[label="27", pos="4.85960359806528,19.4006250638909!", shape = "square"];
28[label="28", pos="3.90180644032257,19.6157056080646!", shape = "square"];
29[label="29", pos="2.93460948910723,19.7835301992956!", shape = "square"];
30[label="30", pos="1.96034280659122,19.9036945334439!", shape = "square"];
31[label="31", pos="0.981353486548363,19.9759091241034!", shape = "square"];
32[label="32", pos="1.22464679914735e-15,20.0!", shape = "square"];
33[label="33", pos="-0.98135348654836,19.9759091241034!", shape = "square"];
34[label="34", pos="-1.96034280659121,19.9036945334439!", shape = "square"];
35[label="35", pos="-2.93460948910723,19.7835301992956!", shape = "square"];
36[label="36", pos="-3.90180644032256,19.6157056080646!", shape = "square"];
37[label="37", pos="-4.85960359806528,19.4006250638909!", shape = "square"];
38[label="38", pos="-5.80569354508924,19.1388067146442!", shape = "square"];
39[label="39", pos="-6.7377970678444,18.8308813036604!", shape = "square"];
40[label="40", pos="-7.65366864730179,18.4775906502257!", shape = "square"];
41[label="41", pos="-8.55110186860564,18.0797858624689!", shape = "square"];
42[label="42", pos="-9.42793473651995,17.6384252869671!", shape = "square"];
43[label="43", pos="-10.2820548838644,17.1545722000054!", shape = "square"];
44[label="44", pos="-11.111404660392,16.6293922460509!", shape = "square"];
45[label="45", pos="-11.9139860898487,16.0641506296129!", shape = "square"];
46[label="46", pos="-12.6878656832729,15.4602090672547!", shape = "square"];
47[label="47", pos="-13.4311790969404,14.8190225070992!", shape = "square"];
48[label="48", pos="-14.1421356237309,14.142135623731!", shape = "square"];
49[label="49", pos="-14.8190225070992,13.4311790969404!", shape = "square"];
50[label="50", pos="-15.4602090672547,12.6878656832729!", shape = "square"];
51[label="51", pos="-16.0641506296129,11.9139860898487!", shape = "square"];
52[label="52", pos="-16.6293922460509,11.111404660392!", shape = "square"];
53[label="53", pos="-17.1545722000054,10.2820548838644!", shape = "square"];
54[label="54", pos="-17.6384252869671,9.42793473651996!", shape = "square"];
55[label="55", pos="-18.0797858624689,8.55110186860564!", shape = "square"];
56[label="56", pos="-18.4775906502257,7.6536686473018!", shape = "square"];
57[label="57", pos="-18.8308813036604,6.73779706784441!", shape = "square"];
58[label="58", pos="-19.1388067146442,5.80569354508925!", shape = "square"];
59[label="59", pos="-19.4006250638909,4.85960359806528!", shape = "square"];
60[label="60", pos="-19.6157056080646,3.90180644032257!", shape = "square"];
61[label="61", pos="-19.7835301992956,2.93460948910724!", shape = "square"];
62[label="62", pos="-19.9036945334439,1.96034280659122!", shape = "square"];
63[label="63", pos="-19.9759091241034,0.98135348654836!", shape = "square"];
64[label="64", pos="-20.0,2.44929359829471e-15!", shape = "square"];
65[label="65", pos="-19.9759091241034,-0.981353486548354!", shape = "square"];
66[label="66", pos="-19.9036945334439,-1.96034280659121!", shape = "square"];
67[label="67", pos="-19.7835301992956,-2.93460948910723!", shape = "square"];
68[label="68", pos="-19.6157056080646,-3.90180644032257!", shape = "square"];
69[label="69", pos="-19.4006250638909,-4.85960359806528!", shape = "square"];
70[label="70", pos="-19.1388067146442,-5.80569354508924!", shape = "square"];
71[label="71", pos="-18.8308813036604,-6.7377970678444!", shape = "square"];
72[label="72", pos="-18.4775906502257,-7.65366864730179!", shape = "square"];
73[label="73", pos="-18.0797858624689,-8.55110186860564!", shape = "square"];
74[label="74", pos="-17.6384252869671,-9.42793473651995!", shape = "square"];
75[label="75", pos="-17.1545722000054,-10.2820548838644!", shape = "square"];
76[label="76", pos="-16.6293922460509,-11.111404660392!", shape = "square"];
77[label="77", pos="-16.0641506296129,-11.9139860898487!", shape = "square"];
78[label="78", pos="-15.4602090672547,-12.6878656832729!", shape = "square"];
79[label="79", pos="-14.8190225070992,-13.4311790969404!", shape = "square"];
80[label="80", pos="-14.142135623731,-14.1421356237309!", shape = "square"];
81[label="81", pos="-13.4311790969404,-14.8190225070992!", shape = "square"];
82[label="82", pos="-12.6878656832729,-15.4602090672547!", shape = "square"];
83[label="83", pos="-11.9139860898487,-16.0641506296129!", shape = "square"];
84[label="84", pos="-11.111404660392,-16.6293922460509!", shape = "square"];
85[label="85", pos="-10.2820548838644,-17.1545722000054!", shape = "square"];
86[label="86", pos="-9.42793473651996,-17.6384252869671!", shape = "square"];
87[label="87", pos="-8.55110186860565,-18.0797858624689!", shape = "square"];
88[label="88", pos="-7.65366864730181,-18.4775906502257!", shape = "square"];
89[label="89", pos="-6.7377970678444,-18.8308813036604!", shape = "square"];
90[label="90", pos="-5.80569354508925,-19.1388067146442!", shape = "square"];
91[label="91", pos="-4.85960359806528,-19.4006250638909!", shape = "square"];
92[label="92", pos="-3.90180644032257,-19.6157056080646!", shape = "square"];
93[label="93", pos="-2.93460948910725,-19.7835301992956!", shape = "square"];
94[label="94", pos="-1.96034280659121,-19.9036945334439!", shape = "square"];
95[label="95", pos="-0.981353486548361,-19.9759091241034!", shape = "square"];
96[label="96", pos="-3.67394039744206e-15,-20.0!", shape = "square"];
97[label="97", pos="0.981353486548353,-19.9759091241034!", shape = "square"];
98[label="98", pos="1.9603428065912,-19.9036945334439!", shape = "square"];
99[label="99", pos="2.93460948910724,-19.7835301992956!", shape = "square"];
100[label="100", pos="3.90180644032257,-19.6157056080646!", shape = "square"];
101[label="101", pos="4.85960359806528,-19.4006250638909!", shape = "square"];
102[label="102", pos="5.80569354508924,-19.1388067146442!", shape = "square"];
103[label="103", pos="6.73779706784439,-18.8308813036604!", shape = "square"];
104[label="104", pos="7.6536686473018,-18.4775906502257!", shape = "square"];
105[label="105", pos="8.55110186860564,-18.0797858624689!", shape = "square"];
106[label="106", pos="9.42793473651995,-17.6384252869671!", shape = "square"];
107[label="107", pos="10.2820548838644,-17.1545722000054!", shape = "square"];
108[label="108", pos="11.111404660392,-16.6293922460509!", shape = "square"];
109[label="109", pos="11.9139860898487,-16.0641506296129!", shape = "square"];
110[label="110", pos="12.6878656832729,-15.4602090672547!", shape = "square"];
111[label="111", pos="13.4311790969404,-14.8190225070992!", shape = "square"];
112[label="112", pos="14.1421356237309,-14.142135623731!", shape = "square"];
113[label="113", pos="14.8190225070992,-13.4311790969404!", shape = "square"];
114[label="114", pos="15.4602090672547,-12.6878656832729!", shape = "square"];
115[label="115", pos="16.0641506296129,-11.9139860898487!", shape = "square"];
116[label="116", pos="16.6293922460509,-11.111404660392!", shape = "square"];
117[label="117", pos="17.1545722000054,-10.2820548838644!", shape = "square"];
118[label="118", pos="17.6384252869671,-9.42793473651996!", shape = "square"];
119[label="119", pos="18.0797858624689,-8.55110186860565!", shape = "square"];
120[label="120", pos="18.4775906502257,-7.65366864730181!", shape = "square"];
121[label="121", pos="18.8308813036604,-6.7377970678444!", shape = "square"];
122[label="122", pos="19.1388067146442,-5.80569354508925!", shape = "square"];
123[label="123", pos="19.4006250638909,-4.85960359806528!", shape = "square"];
124[label="124", pos="19.6157056080646,-3.90180644032257!", shape = "square"];
125[label="125", pos="19.7835301992956,-2.93460948910725!", shape = "square"];
126[label="126", pos="19.9036945334439,-1.96034280659121!", shape = "square"];
127[label="127", pos="19.9759091241034,-0.981353486548362!", shape = "square"];
128[label="128", pos="20.0,-4.89858719658941e-15!", shape = "square"];
25->42
25->71
26->25
26->40
27->30
29->25
29->26
29->27
29->30
29->32
29->40
29->80
32->39
33->28
33->44
33->74
37->34
37->66
37->69
38->60
38->107
40->100
47->30
48->35
48->36
50->35
50->63
51->50
51->96
52->50
53->51
53->96
59->50
59->51
59->52
59->60
60->50
60->63
60->95
67->74
67->114
68->74
70->74
70->126
71->74
71->86
72->70
75->39
77->81
79->73
80->84
82->78
82->114
86->115
87->115
87->121
91->69
91->87
96->30
96->114
101->107
102->108
107->75
107->78
108->95
108->103
111->80
111->114
114->128
115->114
118->128
119->103
121->72
123->116
125->80
126->122
128->96
}
Generating your own node positions is the best solution outside of coming up with a better algorithm or adding weighting to circo by altering the graphviz source.
However, it does defeat the purpose of generating arbitrary graphs with graphviz. This script will use graphviz itself to generate a circle of arbitrary size with user defined formatting, hardcode the position, and then add edges across the center.
#!/bin/bash
# loopgen.sh- generates a plain graphviz loop then hardcodes it and adds to it
# input file format -
# num of nodes
# prefixes for the generated file (format information, labels)
# (blank)
# postfixes for the final file (extra connections, inputscale)
# output - graph with nodes0 to nodex
file=$(<$1)
# trim filename to function name
fun=${1##*/}
fun=${fun%%.*}
# gen is generation function
gen="digraph $fun
{
layout=circo;"
# fin is final function
fin=""
# get the number of inputs
num=$(head -n 1 <<< "$file")
if [ $num -lt 2 ]; then
echo "Bad number of inputs."
exit -1
fi
# increment the lines of the file
file=$(tail -n +2 <<< "$file")
# add all lines up to the first blank line
gen="$gen
$(printf "$file" | awk '!p;/^$/{p=1}')"
# remove all lines before the first blank line
file=$(printf "$file" | awk '/^$/{p=1}p')
# begin producing character-based nodes
i=1
gen="$gen
node0 "
while [ $i -lt $num ]; do
gen="$gen -> node$i"
let i=i+1
done
#finish the loop
gen="$gen -> node0;
}"
# generate, replace circo layout reference, make positions absolute
gen=$(printf "$gen" | dot |
sed -e 's/layout=circo/layout=neato/' -e 's/\(pos=".*\)"/\1!"/g')
# remove trailing brace
gen=$(printf "$gen" | head -n -1)
fin="/* generated with loopgen.sh */
$gen
$file
}"
printf "$fin"
exit 0
Here is an example file.
6
node0 [label="bop it"];
node1 [label="twist it"];
node2 [label="pull it"];
node3 [label="flick it"];
node4 [label="spin it"];
node5 [label="throw it away"];
node2 -> node5 [constraint=false,weight=0];
// this keeps the program from running out of memory
inputscale=72
Running
loopgen.sh input | neato -Tpng > output.png
Results in
Where normally, the same layout would result in
