adjacency_matrix_basics.py

class Graph(object):

     # number of vertices
    numberOfVertices = 0
 
     # adjacency matrix

    
    def __init__(self, size):
        self.adjMatrix = []
        for i in range(size):
            self.adjMatrix.append([0 for i in range(size)])
        print(self.adjMatrix)
        self.size = size

    #methods for (1) adding a vertex; (2) adding an edge; (3) removing an edge; and (4) printing the
    #matrix should appear here

# this method is for adding vertex
    def VertexAddition(self):
            
            # increasing the number of vertices
            self.numberOfVertices = self.numberOfVertices + 1
            
            # initializing the new elements to 0
            for i in range(0, self.numberOfVertices):
                self.adjMatrix[i][self.numberOfVertices-1]= 0
                self.adjMatrix[self.numberOfVertices-1][i]= 0

    #This function adds an edge by accepting the adjacentMatrix, u and v as a parameter
    def EdgeAddition(adjMatrix, u, v):
    # To add i only append the values.
        adjMatrix[u].append(v)
        adjMatrix[v].append(u)
        
    def EdgeDeletion(adjacentValues,  u,  v):
        
       
        # Here am looping through the first section while at the same time removing the second element
        for x in range(len(adjacentValues[u])):
        
            if (adjacentValues[u][x] == v):
                
                adjacentValues[u].pop(x);
                break;
        
        # Looping through the last section and removing the first element
        for x in range(len(adjacentValues[v])):
        
            if (adjacentValues[v][x] == u):
                
                adjacentValues[v].pop(x);
                break;




#remember list indexing - this is 1 out, unless we start the matrix at 0 (not a +ve integer)     
def main():
        g = Graph(6)

            
if __name__ == '__main__':
   main()