clean up code

main.py

@@ -25,19 +25,19 @@ def run_pagerank(matrix_path, epsilon, alpha):
         match = re.search(r"Read and convert matrix: (\d+\.\d+) seconds", output)
         data["read_time"] = float(match.group(1)) if match else None
 
-        match = re.search(r"Pagerank: (\d+) Iterations", output)
+        match = re.search(r"Pagerank \(power\): (\d+) Iterations", output)
         data["pagerank_iterations"] = int(match.group(1)) if match else None
 
-        match = re.search(r"Pagerank: (\d+\.\d+) seconds", output)
+        match = re.search(r"Pagerank \(power\): (\d+\.\d+) seconds", output)
         data["pagerank_time"] = float(match.group(1)) if match else None
 
-        match = re.search(r"Gauss-Seidel: (\d+) Iterations", output)
+        match = re.search(r"Gauß-Seidel: (\d+) Iterations", output)
         data["gauss_seidel_iterations"] = int(match.group(1)) if match else None
 
-        match = re.search(r"Gauss-Seidel: (\d+\.\d+) seconds", output)
+        match = re.search(r"Gauß-Seidel: (\d+\.\d+) seconds", output)
         data["gauss_seidel_time"] = float(match.group(1)) if match else None
 
-        match = re.search(r"Difference norm Pagerank and Gauss-Seidel: (\d+\.\d+)", output)
+        match = re.search(r"Difference norm Pagerank power and Gauß-Seidel: (\d+\.\d+)", output)
         data["diff_norm"] = float(match.group(1)) if match else None
 
         return data

src/gauss_seidel.c

@@ -72,13 +72,10 @@ double* gauss_seidel_pagerank(const SparseMatrix *matrix, double epsilon, double
         // 5. convergence
         diff = diff_norm_vector(x, x_old, N);
 
-        // if ((++iter) % 10 == 0) {
-        //     printf("Gauss-Seidel Iteration %d: diff = %.16f\n", iter, diff);
-        // }
         ++iter;
     } while (diff > epsilon);
 
-    printf("Gauss-Seidel: %d Iterations\n", iter);
+    printf("Gauß-Seidel: %d Iterations\n", iter);
 
     free(x_old);
     free(f);

src/main.c

@@ -12,34 +12,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
-
+#include "ranking_utils.h"
-static double *values_for_sort;
-int cmp_desc(const void *a, const void *b) {
-    int ia = *(const int*)a;
-    int ib = *(const int*)b;
-    if (values_for_sort[ia] < values_for_sort[ib]) return  1;
-    if (values_for_sort[ia] > values_for_sort[ib]) return -1;
-    return 0;
-}
-
-void print_top_k(const char *name, double *pi, int n, int k) {
-    int *idx = malloc(n * sizeof(int));
-    if(!idx) {
-        fprintf(stderr, "malloc failed\n");
-        return;
-    }
-    for (int i = 0; i < n; i++) idx[i] = i;
-
-    values_for_sort = pi;
-    qsort(idx, n, sizeof(int), cmp_desc);
-
-    printf("Top %d entries of %s:\n", k, name);
-    for (int i = 0; i < k && i < n; i++) {
-        int node = idx[i];
-        printf("  %2d: node %d → %.8f\n", i+1, node, pi[node]);
-    }
-    free(idx);
-}
 
 
 void test_stationary_distribution(const char *path, double epsilon, double alpha) {
@@ -62,21 +35,21 @@ void test_stationary_distribution(const char *path, double epsilon, double alpha
     gettimeofday(&tvstart, NULL);
     double *pi_power = pagerank(matrix, epsilon, alpha);
     gettimeofday(&tvend, NULL);
-    print_time_diff("Pagerank", &tvstart, &tvend);
+    print_time_diff("Pagerank (power)", &tvstart, &tvend);
 
     gettimeofday(&tvstart, NULL);
     double *pi_new = gauss_seidel_pagerank(matrix, epsilon, alpha);
 
     gettimeofday(&tvend, NULL);
-    print_time_diff("Gauss-Seidel", &tvstart, &tvend);
+    print_time_diff("Gauß-Seidel", &tvstart, &tvend);
 
     double diff = diff_norm_vector(pi_power, pi_new, matrix->num_nodes);
-    printf("Difference norm Pagerank and Gauss-Seidel: %.16f\n", diff);
+    printf("Difference norm Pagerank power and Gauß-Seidel: %.16f\n", diff);
 
     int n = matrix->num_nodes;
     int k = 10;
     print_top_k("pagerank (power)", pi_power, n, k);
-    print_top_k("pagerank (Gauss–Seidel)", pi_new,    n, k);
+    print_top_k("pagerank (Gauß–Seidel)", pi_new, n, k);
 
     free(pi_power);
     free(pi_new);

src/power_algorithm.c

@@ -64,14 +64,11 @@ double* pagerank(const SparseMatrix *matrix, double epsilon, double alpha) {
         pi = pi_new;
         pi_new = malloc(vec_size);
 
-        // if ((++iter)%1 == 0) {
-        //     printf("Iteration %d: diff = %.16f\n", iter, diff);
-        // }
         ++iter;
         free(temp);
     } while (diff > epsilon);
 
-    printf("Pagerank: %d Iterations\n", iter);
+    printf("Pagerank (power): %d Iterations\n", iter);
 
     free(pi_new);
     free(f);

src/ranking_utils.c

@@ -0,0 +1,40 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "ranking_utils.h"
+
+typedef struct {
+    int index;
+    double value;
+} IndexedValue;
+
+// descending order sort for indexed stationary distribution values
+static int cmp_desc_struct(const void *a, const void *b) {
+    const IndexedValue *ia = (const IndexedValue *)a;
+    const IndexedValue *ib = (const IndexedValue *)b;
+    if (ia->value < ib->value) return 1;
+    if (ia->value > ib->value) return -1;
+    return 0;
+}
+
+void print_top_k(const char *name, double *pi, int n, int k) {
+
+    IndexedValue *ivals = malloc(n * sizeof(IndexedValue));
+    if (!ivals) {
+        fprintf(stderr, "malloc failed\n");
+        return;
+    }
+
+    for (int i = 0; i < n; i++) {
+        ivals[i].index = i;
+        ivals[i].value = pi[i];
+    }
+
+    qsort(ivals, n, sizeof(IndexedValue), cmp_desc_struct);
+
+    printf("Top %d entries of %s:\n", k, name);
+    for (int i = 0; i < k && i < n; i++) {
+        printf("  %2d: node %d -> %.8f\n", i + 1, ivals[i].index, ivals[i].value);
+    }
+
+    free(ivals);
+}

src/ranking_utils.h

@@ -0,0 +1,6 @@
+#ifndef RANKING_UTILS_H
+#define RANKING_UTILS_H
+
+void print_top_k(const char *name, double *pi, int n, int k);
+
+#endif