3. The method as claimed in claim 2 , wherein said criterion is satisfied for a given vertex v if a characteristic vector A M i (v) of the neighborhood of the vertex v in the current minor M i of the graph and the characteristic vector A G (v) of the neighborhood of the vertex v in the constructed graph G, satisfy the following relation: 
 | A M i ( v )|≦β| A g ( v )− A M i ( v )| where β is a convergence parameter.
3. The method as claimed in claim 2 , wherein said criterion is satisfied for a given vertex v if a characteristic vector A M i (v) of the neighborhood of the vertex v in the current minor M i of the graph and the characteristic vector A G (v) of the neighborhood of the vertex v in the constructed graph G, satisfy the following relation: 
 | A M i ( v )|≦β| A g ( v )− A M i ( v )| where β is a convergence parameter. 4. The method as claimed in claim 3 , further comprising: adjusting a value of the convergence parameter β to a predefined initial value β 0 before execution of the iterative process of step b); readjusting the value of the convergence parameter β after an iteration if this iteration has not culminated in modification of the current minor M i of the graph and if the predefined number N of vertices is not reached for the current minor M i of the graph; and reinitializing the value of the convergence parameter β to its initial value β 0 after an iteration has culminated in the modification of the current minor M i of the graph.