Add graph references

references/igraph-1.0.1/tests/benchmarks/intersection.c

@@ -0,0 +1,87 @@
+/*
+   igraph library.
+   Copyright (C) 2024  The igraph development team <igraph@igraph.org>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <igraph.h>
+
+#include "bench.h"
+
+void rand_vec(igraph_vector_int_t *v, igraph_int_t n, igraph_int_t k) {
+    igraph_vector_int_resize(v, n);
+    for (igraph_int_t i=0; i < n; i++) {
+        VECTOR(*v)[i] = RNG_INTEGER(0, k);
+    }
+}
+
+void run_bench(int i, int n, int r) {
+    igraph_vector_int_t a, b;
+    igraph_int_t na = n, nb = r*n;
+    int rep = 300000000 / nb;
+    char msg[255];
+
+    igraph_vector_int_init(&a, na);
+    igraph_vector_int_init(&b, nb);
+
+    rand_vec(&a, na, nb);
+    igraph_vector_int_sort(&a);
+    rand_vec(&b, nb, nb);
+    igraph_vector_int_sort(&b);
+
+    snprintf(msg, sizeof(msg) / sizeof(msg[0]),
+             "%2d n = %5d, r = %3d, %dx", i, n, r, rep);
+
+    /* 'volatile' is needed to prevent the compiler from optimizing
+     * away multiple calls to the function with the same parameters within REPEAT.
+     * This would normally happen due to the use of IGRAPH_FUNCATTR_PURE.
+     * ATTENTION! 'volatile', when used this way, may not prevent this optimization
+     * with future compiler versions. */
+    volatile igraph_int_t res;
+    BENCH(msg, REPEAT(res = igraph_vector_int_intersection_size_sorted(&a, &b), rep));
+    (void) res;  /* silence unused-but-set-variable warning */
+
+    igraph_vector_int_destroy(&a);
+    igraph_vector_int_destroy(&b);
+}
+
+int main(void) {
+    int i = 0;
+
+    igraph_rng_seed(igraph_rng_default(), 137);
+    BENCH_INIT();
+
+#define BENCHSET(n) \
+    run_bench(++i, n, 1); \
+    run_bench(++i, n, 3); \
+    run_bench(++i, n, 10); \
+    run_bench(++i, n, 30); \
+    run_bench(++i, n, 100); \
+    printf("\n");
+
+    BENCHSET(1);
+    BENCHSET(3);
+    BENCHSET(10);
+    BENCHSET(30);
+    BENCHSET(100);
+    BENCHSET(300);
+    BENCHSET(1000);
+    BENCHSET(3000);
+    BENCHSET(10000);
+    BENCHSET(30000);
+    BENCHSET(100000);
+
+    return 0;
+}