1 files changed, 198 insertions, 0 deletions
diff --git a/examples/src/models/ising/wolff_ising.cpp b/examples/src/models/ising/wolff_ising.cpp
new file mode 100644
index 0000000..5bdaa82
--- /dev/null
+++ b/examples/src/models/ising/wolff_ising.cpp
@@ -0,0 +1,198 @@
+
+#include <getopt.h>
+#include <stdio.h>
+
+// if you have GLUT installed, you can see graphics!
+#ifdef HAVE_GLUT
+#include <GL/glut.h>
+#endif
+
+// include your group and spin space
+#include "z2.hpp"
+#include "ising.hpp"
+
+// finite_states.h can be included for spin types that have special variables
+// defined, and it causes wolff execution to use precomputed bond probabilities
+#include <wolff/finite_states.hpp>
+
+#include <randutils/randutils.hpp>
+
+// measure.hpp contains useful functions for saving timeseries to files
+#include <measure.hpp>
+
+// include wolff.hpp
+#include <wolff.hpp>
+
+int main(int argc, char *argv[]) {
+
+  count_t N = (count_t)1e4;
+
+  D_t D = 2;
+  L_t L = 128;
+  double T = 2.26918531421;
+  double H = 0.0;
+
+  bool silent = false;
+  bool draw = false;
+  bool N_is_sweeps = false;
+  unsigned int window_size = 512;
+
+  // don't measure anything by default
+  unsigned char measurement_flags = 0;
+
+  int opt;
+
+  while ((opt = getopt(argc, argv, "N:D:L:T:H:sdw:M:S")) != -1) {
+    switch (opt) {
+    case 'N': // number of steps
+      N = (count_t)atof(optarg);
+      break;
+    case 'D': // dimension
+      D = atoi(optarg);
+      break;
+    case 'L': // linear size
+      L = atoi(optarg);
+      break;
+    case 'T': // temperature 
+      T = atof(optarg);
+      break;
+    case 'H': // external field
+      H = atof(optarg);
+      break;
+    case 's': // don't print anything during simulation. speeds up slightly
+      silent = true;
+      break;
+    case 'S':
+      N_is_sweeps = true;
+      break;
+    case 'd':
+#ifdef HAVE_GLUT
+      draw = true;
+      break;
+#else
+      printf("You didn't compile this with the glut library installed!\n");
+      exit(EXIT_FAILURE);
+#endif
+    case 'w':
+      window_size = atoi(optarg);
+      break;
+    case 'M':
+      measurement_flags ^= 1 << atoi(optarg);
+      break;
+    default:
+      exit(EXIT_FAILURE);
+    }
+  }
+
+  // get nanosecond timestamp for unique run id
+  unsigned long timestamp;
+
+  {
+    struct timespec spec;
+    clock_gettime(CLOCK_REALTIME, &spec);
+    timestamp = spec.tv_sec*1000000000LL + spec.tv_nsec;
+  }
+
+  // initialize random number generator
+  randutils::auto_seed_128 seeds;
+  std::mt19937 rng{seeds};
+
+  // define spin-spin coupling
+  std::function <double(const ising_t&, const ising_t&)> Z = [] (const ising_t& s1, const ising_t& s2) -> double {
+    if (s1.x == s2.x) {
+      return 1.0;
+    } else {
+      return -1.0;
+    }
+  };
+
+  // define spin-field coupling
+  std::function <double(const ising_t&)> B = [=] (const ising_t& s) -> double {
+    if (s.x) {
+      return -H;
+    } else {
+      return H;
+    }
+  };
+
+  // initialize state object
+#ifndef NOFIELD
+  state_t <z2_t, ising_t> s(D, L, T, Z, B);
+#else
+  state_t <z2_t, ising_t> s(D, L, T, Z);
+#endif
+
+  // define function that generates self-inverse rotations
+  std::function <z2_t(std::mt19937&, ising_t)> gen_R = [] (std::mt19937&, const ising_t& s) -> z2_t {
+    return z2_t(true);
+  };
+
+  FILE **outfiles = measure_setup_files(measurement_flags, timestamp);
+
+  std::function <void(const state_t<z2_t, ising_t>&)> other_f;
+  uint64_t sum_of_clusterSize = 0;
+
+  if (N_is_sweeps) {
+    other_f = [&] (const state_t<z2_t, ising_t>& s) {
+      sum_of_clusterSize += s.last_cluster_size;
+    };
+  } else if (draw) {
+#ifdef HAVE_GLUT
+    // initialize glut
+    glutInit(&argc, argv);
+    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
+    glutInitWindowSize(window_size, window_size);
+    glutCreateWindow("wolff");
+    glClearColor(0.0,0.0,0.0,0.0);
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    gluOrtho2D(0.0, L, 0.0, L);
+
+    other_f = [] (const state_t <z2_t, ising_t>& s) {
+      glClear(GL_COLOR_BUFFER_BIT);
+      for (v_t i = 0; i < pow(s.L, 2); i++) {
+        if (s.spins[i].x == s.R.x) {
+          glColor3f(0.0, 0.0, 0.0);
+        } else {
+          glColor3f(1.0, 1.0, 1.0);
+        }
+        glRecti(i / s.L, i % s.L, (i / s.L) + 1, (i % s.L) + 1);
+      }
+      glFlush();
+    };
+#endif
+  } else {
+    other_f = [] (const state_t<z2_t, ising_t>& s) {};
+  }
+
+  std::function <void(const state_t<z2_t, ising_t>&)> measurements = measure_function_write_files(measurement_flags, outfiles, other_f);
+
+  // add line to metadata file with run info
+  {
+    FILE *outfile_info = fopen("wolff_metadata.txt", "a");
+
+    fprintf(outfile_info, "<| \"ID\" -> %lu, \"MODEL\" -> \"ISING\", \"q\" -> 2, \"D\" -> %" PRID ", \"L\" -> %" PRIL ", \"NV\" -> %" PRIv ", \"NE\" -> %" PRIv ", \"T\" -> %.15f, \"H\" -> %.15f |>\n", timestamp, s.D, s.L, s.nv, s.ne, T, H);
+
+    fclose(outfile_info);
+  }
+
+  // run wolff for N cluster flips
+  if (N_is_sweeps) {
+    count_t N_rounds = 0;
+    printf("\n");
+    while (sum_of_clusterSize < N * s.nv) {
+      printf("\033[F\033[J\033[F\033[JWOLFF: sweep %" PRIu64 " / %" PRIu64 ": E = %.2f, S = %" PRIv "\n", (count_t)((double)sum_of_clusterSize / (double)s.nv), N, s.E, s.last_cluster_size);
+      wolff(N, s, gen_R, measurements, rng, silent);
+      N_rounds++;
+    }
+    printf("\033[F\033[J\033[F\033[JWOLFF: sweep %" PRIu64 " / %" PRIu64 ": E = %.2f, S = %" PRIv "\n\n", (count_t)((double)sum_of_clusterSize / (double)s.nv), N, s.E, s.last_cluster_size);
+  } else {
+    wolff(N, s, gen_R, measurements, rng, silent);
+  }
+
+  measure_free_files(measurement_flags, outfiles);
+
+  return 0;
+
+}
+