Gravitational Search Algorithm

teeline · algorithms/gsa

Each candidate TSP tour is an agent with a mass proportional to its fitness — better tours weigh more. Every step, the active agent is pulled toward the k-best (heaviest) neighbours via swap-move velocity. The gravitational constant G decays over epochs, shifting the swarm from broad exploration toward fine-grained exploitation.

Agents

01800

#0 · dist=1800 · mass=0.315

12331

#1 · dist=2331 · mass=0.036

22334

#2 · dist=2334 · mass=0.034

32094

#3 · dist=2094 · mass=0.160

42065

#4 · dist=2065 · mass=0.175

52155

#5 · dist=2155 · mass=0.128

62111

#6 · dist=2111 · mass=0.151

72399

#7 · dist=2399 · mass=0.000

● gbest tour● active agent● swarm● city kbest source

Press Step or Run to begin

G (gravitational constant) = 20.00

High — broad exploration

epoch

step

0/8

gbest dist

1799.6

avg dist

2161

Agents = 8

Balanced swarm size

Speed