how making circle moving node to node after Ant colony make decision with probability ?

hello... i have some problem about Ant colony Algorithm, how to calculate the probability ant colony if the decision each node is different, every node just can move four direction, for example ant at node 1 now the ant make decision to choose next node. where : d= [ 0 30 40 20 30 ]

if we have decicion of ant will move next node, how to move that cirle in node 1 to node ant will chose this code for position of the circle

clc

clear all

xnode=[20 50 80 50 50];

ynode=[60 60 60 30 90];

xRobot=[50];

yRobot=[60];

rNode=1

for i=1:5

d=rNode*2;

px = xnode(i)-rNode;

py = ynode(i)-rNode;

h = rectangle ('Position',[ px py d d], 'Curvature',[1,1],'FaceColor','y','EdgeColor','r');

daspect([1,1,1]);

end

rRobot=2;

d=rRobot*2;

px = xRobot-rRobot;

py = yRobot-rRobot;

h = rectangle ('Position',[ px py d d], 'Curvature',[1,1],'FaceColor','b','EdgeColor','b');

daspect([1,1,1]);

if someone who know that problem,please help me,