tg_eigenvector_cent.gsql

CREATE DISTRIBUTED QUERY tg_eigenvector_cent(SET<STRING> v_type_set, SET<STRING> e_type_set, INT maximum_iteration = 100, FLOAT conv_limit = 0.000001,
    INT top_k = 100, BOOL print_results = True, STRING result_attribute = "",STRING file_path = ""
    ) SYNTAX V1 {

    /*
        First Author: <First Author Name>
        First Commit Date:  <First Commit Date>

        Recent Author: <Recent Commit Author Name>
        Recent Commit Date: <Recent Commit Date>


        Repository:
            https://github.com/tigergraph/gsql-graph-algorithms/tree/master/algorithms/Centrality

        Maturity:
            Production

        Description: 
            Compute eigenvector Centrality for each VERTEX. 

        Publications:
            NA

        TigerGraph Documentation:
            https://docs.tigergraph.com/graph-ml/current/centrality-algorithms/eigenvector-centrality

        Parameters:
            v_type_set:
                vertex types to traverse
            e_type_set:
                edge types to traverse
            maximum_iteration:
                max iteration
            conv_limit:
                convergence limitation
            top_k:
                report only this many top scores
            print_results:
                If True, print the results
            result_attribute:
                attribute to write result to
            file_path:
                file to write CSV output to
    */
     
    TYPEDEF TUPLE<VERTEX Vertex_ID, FLOAT score> Vertex_Score;
    HeapAccum<Vertex_Score>(top_k, score DESC) @@top_scores_heap;
    SumAccum<FLOAT> @@sum_squares_eigen_values;
    SumAccum<FLOAT> @sum_received_value;
    SumAccum<FLOAT> @sum_eigen_value = 1.0;
    SumAccum<FLOAT> @@sum_cur_norm_values;
    SumAccum<FLOAT> @@sum_prev_norm_values;
    FLOAT conv_value = 9999;
    FILE f (file_path);
    Start = {v_type_set};
    WHILE conv_value > conv_limit LIMIT maximum_iteration DO
        @@sum_squares_eigen_values = 0;
        @@sum_cur_norm_values = 0;
        V = SELECT s 
            FROM Start:s - (e_type_set:e) - v_type_set:t
            ACCUM t.@sum_received_value += s.@sum_eigen_value;
        V = SELECT s 
            FROM Start:s
            POST-ACCUM s.@sum_eigen_value = s.@sum_received_value,
                       @@sum_squares_eigen_values += s.@sum_eigen_value * s.@sum_eigen_value,
                       s.@sum_received_value = 0;
       
        V = SELECT s 
            FROM V:s
            POST-ACCUM s.@sum_eigen_value = s.@sum_eigen_value / sqrt(@@sum_squares_eigen_values),
                       @@sum_cur_norm_values += s.@sum_eigen_value;
        
        conv_value = abs(@@sum_cur_norm_values - @@sum_prev_norm_values);
        @@sum_prev_norm_values = @@sum_cur_norm_values;
                               
    END;
    #Output
    IF file_path != "" THEN
        f.println("Vertex_ID", "egien vector");
    END;
    Start = SELECT s 
            FROM Start:s
            ACCUM 
                IF s.@sum_eigen_value==1.0 THEN 
                    s.@sum_eigen_value+=-1 
                END
      POST-ACCUM 
          IF result_attribute != "" THEN 
                    s.setAttr(result_attribute, s.@sum_eigen_value) 
                END,
      
    IF print_results THEN 
                    @@top_scores_heap += Vertex_Score(s, s.@sum_eigen_value) 
                END,
      
    IF file_path != "" THEN 
                    f.println(s, s.@sum_eigen_value) 
                END;

    IF print_results THEN
        PRINT @@top_scores_heap AS top_scores;
    END;

}