Getting Error not enough input argument while ruuning the below code.

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function [T, cost] = MinimumSpanningTree (CostMatrix);
% The function takes CostMatrix as input and returns the minimum spanning
% tree T and cost of T
% Uses Kruskal's Algorithm
% Extract the edge weights from the cost matrix
% Sort the edges in a non decreasing order of weights
n = size (CostMatrix,1); %Number of vertices
EdgeWeights = 0; %Edges and corresponding weights
EdgeWeightsCounter = 0;
for i = 1:n
for j = (i+1):n
if ((CostMatrix(i,j))~=inf)
EdgeWeightsCounter = EdgeWeightsCounter + 1;
EdgeWeights(EdgeWeightsCounter,1) = CostMatrix(i,j);
EdgeWeights(EdgeWeightsCounter,2) = i;
EdgeWeights(EdgeWeightsCounter,3) = j;
end
end
end
SortedEdgeWeights = 0;
SortedEdgeWeights = sortrows(EdgeWeights);
% First column of SortedEdgeWeights are the weights
% Second and third column are the vertices that the edges connect
m = size(SortedEdgeWeights,1); % number of edges
% We use the Disjoint sets data structures to detect cycle while adding new
% edges. Union by Rank with path compression is implemented here.
% Assign parent pointers to each vertex. Initially each vertex points to
% itself. Now we have a conceptual forest of n trees representing n disjoint
% sets
global ParentPointer ;
ParentPointer = 0;
ParentPointer(1:n) = 1:n;
% Assign a rank to each vertex (root of each tree). Initially all vertices
% have the rank zero.
TreeRank = 0;
TreeRank(1:n) = 0;
% Visit each edge in the sorted edges array
% If the two end vertices of the edge are in different sets (no cycle), add
% the edge to the set of edges in minimum spanning tree
MSTreeEdges = 0;
MSTreeEdgesCounter = 0; i = 1;
while ((MSTreeEdgesCounter < (n-1)) && (i<=m))
% Find the roots of the trees that the selected edge's two vertices
% belong to. Also perform path compression.
root1=0; root2=0; temproot=0;
temproot = SortedEdgeWeights(i,2);
root1 = FIND_PathCompression(temproot);
temproot = SortedEdgeWeights(i,3);
root2 = FIND_PathCompression(temproot);
if (root1 ~= root2)
MSTreeEdgesCounter = MSTreeEdgesCounter + 1;
MSTreeEdges(MSTreeEdgesCounter,1:3) = SortedEdgeWeights(i,:);
if (TreeRank(root1)>TreeRank(root2))
ParentPointer(root2)=root1;
else
if (TreeRank(root1)==TreeRank(root2))
TreeRank(root2)=TreeRank(root2) + 1;
end
ParentPointer(root1)=root2;
end
end
i = i + 1;
end
cost = sum (MSTreeEdges(:,1));
MSTreeEdgesCounter = 0;
T = 0;
T(1:n,1:n)=0;
while (MSTreeEdgesCounter < (n-1))
MSTreeEdgesCounter = MSTreeEdgesCounter + 1; T(MSTreeEdges(MSTreeEdgesCounter,2),MSTreeEdges(MSTreeEdgesCounter,3))=1; T(MSTreeEdges(MSTreeEdgesCounter,3),MSTreeEdges(MSTreeEdgesCounter,2))=1;
end
%T
%cost

Accepted Answer

Azzi Abdelmalek
Azzi Abdelmalek on 26 Jul 2014
Save this function file as MinimumSpanningTree.m
in Matlab Windows Command type:
CostMatrix= % provide your data
[T, cost] = MinimumSpanningTree (CostMatrix)
  1 Comment
priyanka
priyanka on 26 Jul 2014
Edited: priyanka on 26 Jul 2014
Thank You So much. Can you tell me the code to generate a graph of n nodes and find the distance between these n nodes

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More Answers (1)

aosheng xuanyuan
aosheng xuanyuan on 22 Apr 2015
You lose a function, the function is FIND_PathCompression ( ).

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