2 files changed, 493 insertions, 0 deletions
diff --git a/examples/src/tools/CMakeLists.txt b/examples/src/tools/CMakeLists.txt
new file mode 100644
index 0000000..1c73c2d
--- /dev/null
+++ b/examples/src/tools/CMakeLists.txt
@@ -0,0 +1,7 @@
+
+find_library(fftw REQUIRED NAMES fftw3)
+
+add_executable(analyze_correlations analyze_correlations.cpp)
+
+target_link_libraries(analyze_correlations fftw3 wolff)
+
diff --git a/examples/src/tools/analyze_correlations.cpp b/examples/src/tools/analyze_correlations.cpp
new file mode 100644
index 0000000..abeaff3
--- /dev/null
+++ b/examples/src/tools/analyze_correlations.cpp
@@ -0,0 +1,486 @@
+
+#include <wolff/types.h>
+#include <cmath>
+#include <cstring>
+#include <stdio.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <fftw3.h>
+
+template <class T>
+double mean(int N, T *data) {
+  double total = 0;
+  for (int i = 0; i < N; i++) {
+    total += (double)data[i];
+  }
+
+  return total / N;
+}
+
+double squared_mean(int N, double *data) {
+  double total = 0;
+  for (int i = 0; i < N; i++) {
+    total += pow(data[i], 2);
+  }
+
+  return total / N;
+}
+
+double central_moment(int N, double *data, double mean, int m) {
+  double total = 0;
+  for (int i = 0; i < N; i++) {
+    total += pow(data[i] - mean, m);
+  }
+
+  return total / N;
+}
+
+void compute_OO(int N, fftw_plan forward_plan, double *forward_data, fftw_plan reverse_plan, double *reverse_data) {
+
+  fftw_execute(forward_plan);
+
+  reverse_data[0] = forward_data[0] * forward_data[0];
+  reverse_data[N / 2] = forward_data[N/2] * forward_data[N/2];
+
+  for (count_t i = 1; i < N / 2; i++) {
+    reverse_data[i] = pow(forward_data[i], 2) + pow(forward_data[N - i], 2);
+    reverse_data[N - i] = 0;
+  }
+
+  fftw_execute(reverse_plan);
+
+}
+
+double finite_energy(q_t nb, double *J, q_t q, double *H, v_t nv, v_t ne, uint32_t *bo, uint32_t *so) {
+  double energy = 0;
+
+  v_t tot = 0;
+  for (q_t i = 0; i < nb - 1; i++) {
+    energy -= J[i] * bo[i];
+    tot += bo[i];
+  }
+
+  energy -= J[nb - 1] * (ne - tot);
+
+  tot = 0;
+  for (q_t i = 0; i < q - 1; i++) {
+    energy -= H[i] * so[i];
+    tot += so[i];
+  }
+
+  energy -= H[q - 1] * (nv - tot);
+
+  return energy;
+}
+
+int main (int argc, char *argv[]) {
+  count_t drop = (count_t)1e4;
+  count_t length = (count_t)1e4;
+  bool speedy_drop = false;
+  bool from_stdin = false;
+  bool oldstyle = false;
+
+  int opt;
+
+  while ((opt = getopt(argc, argv, "d:l:spo")) != -1) {
+    switch (opt) {
+      case 'd':
+        drop = (count_t)atof(optarg);
+        break;
+      case 'l':
+        length = (count_t)atof(optarg);
+        break;
+      case 's':
+        speedy_drop = true;
+        break;
+      case 'p':
+        from_stdin = true;
+        break;
+      case 'o':
+        oldstyle = true;
+        break;
+      default:
+        exit(EXIT_FAILURE);
+    }
+  }
+  FILE *metadata;
+
+  fftw_set_timelimit(1);
+
+  if (from_stdin) {
+    metadata = stdin;
+  } else {
+    metadata = fopen("wolff_metadata.txt", "r");
+  }
+
+  if (metadata == NULL) {
+    printf("Metadata file not found. Make sure you are in the correct directory!\n");
+    exit(EXIT_FAILURE);
+  }
+
+  unsigned long id;
+  char *model = (char *)malloc(32 * sizeof(char));
+
+  if (model == NULL) {
+    printf("Malloc failed.\n");
+    exit(EXIT_FAILURE);
+  }
+
+  q_t q;
+  D_t D;
+  L_t L;
+  v_t nv, ne;
+
+ while (EOF != fscanf(metadata, "<| \"ID\" -> %lu, \"MODEL\" -> \"%[^\"]\", \"q\" -> %" SCNq ", \"D\" -> %" SCND ", \"L\" -> %" SCNL ", \"NV\" -> %" SCNv ", \"NE\" -> %" SCNv ", ", &id, model, &q, &D, &L, &nv, &ne)) {
+
+   printf("%lu: Processing...\n", id);
+
+//   bool is_finite = 0 == strcmp(model, "ISING") || 0 == strcmp(model, "POTTS") || 0 == strcmp(model, "CLOCK");
+
+    if (oldstyle) {
+      q_t nb;
+      double T;
+      fscanf(metadata, "\"NB\" -> %" SCNq ", \"T\" -> %lf, \"J\" -> {", &nb, &T);
+      double *J = (double *)malloc(nb * sizeof(double));
+      double *H = (double *)malloc(q * sizeof(double));
+
+      if (J == NULL || H == NULL) {
+        printf("%lu: Malloc failed.\n", id);
+        break;
+      }
+
+      for (q_t i = 0; i < nb - 1; i++) {
+        fscanf(metadata, "%lf, ", &(J[i]));
+      }
+      fscanf(metadata, "%lf}, \"H\" -> {", &(J[nb - 1]));
+      for (q_t i = 0; i < q - 1; i++) {
+        fscanf(metadata, "%lf, ", &(H[i]));
+      }
+      fscanf(metadata, "%lf} |>\n", &(H[q - 1]));
+
+      char *filename_M = (char *)malloc(128 * sizeof(char));
+      char *filename_B = (char *)malloc(128 * sizeof(char));
+      char *filename_S = (char *)malloc(128 * sizeof(char));
+
+      if (filename_M == NULL || filename_B == NULL || filename_S == NULL) {
+        printf("%lu: Malloc failed.\n", id);
+        break;
+      }
+
+      sprintf(filename_M, "wolff_%lu_M.dat", id);
+      sprintf(filename_B, "wolff_%lu_B.dat", id);
+      sprintf(filename_S, "wolff_%lu_S.dat", id);
+
+      FILE *file_M = fopen(filename_M, "rb");
+      FILE *file_B = fopen(filename_B, "rb");
+      FILE *file_S = fopen(filename_S, "rb");
+
+      if (file_M == NULL || file_B == NULL || file_S == NULL) {
+        printf("%lu: Opening data file failed.\n", id);
+        break;
+      }
+
+      fseek(file_S, 0, SEEK_END);
+      unsigned long N = ftell(file_S) / sizeof(uint32_t);
+      fseek(file_S, 0, SEEK_SET);
+
+      if (speedy_drop) {
+        drop = N - pow(2, floor(log(N) / log(2)));
+      } else {
+        if (N % 2 == 1 && drop % 2 == 0) {
+          drop++; // make sure M is even
+        }
+      }
+
+      if (N <= drop) {
+        printf("\033[F%lu: Number of steps %lu is less than %" PRIcount ", nothing done.\n", id, N, drop);
+      } else {
+        int M = N - drop;
+
+        double M_f = (double)M;
+
+        if (length > M) {
+          length = M;
+        }
+
+        double *forward_data = (double *)fftw_malloc(M * sizeof(double));
+        fftw_plan forward_plan = fftw_plan_r2r_1d(M, forward_data, forward_data, FFTW_R2HC, 0);
+        double *reverse_data = (double *)fftw_malloc(M * sizeof(double));
+        fftw_plan reverse_plan = fftw_plan_r2r_1d(M, reverse_data, reverse_data, FFTW_HC2R, 0);
+
+
+        uint32_t *data_S = (uint32_t *)malloc(N * sizeof(uint32_t));
+        fread(data_S, N, sizeof(uint32_t), file_S);
+        for (count_t i = 0; i < M; i++) {
+          forward_data[i] = (double)data_S[drop + i];
+        }
+        free(data_S);
+        double mean_S = mean(M, forward_data);
+        double squaredMean_S = squared_mean(M, forward_data);
+        double moment2_S = central_moment(M, forward_data, mean_S, 2);
+        double moment4_S = central_moment(M, forward_data, mean_S, 4);
+
+        compute_OO(M, forward_plan, forward_data, reverse_plan, reverse_data);
+
+        sprintf(filename_S, "wolff_%lu_S_OO.dat", id);
+
+        FILE *file_S = fopen(filename_S, "wb");
+        fwrite(&M_f, sizeof(double), 1, file_S);
+        fwrite(&mean_S, sizeof(double), 1, file_S);
+        fwrite(&squaredMean_S, sizeof(double), 1, file_S);
+        fwrite(&moment2_S, sizeof(double), 1, file_S);
+        fwrite(&moment4_S, sizeof(double), 1, file_S);
+        fwrite(reverse_data, sizeof(double), length, file_S);
+        fclose(file_S);
+
+        uint32_t *data_B = (uint32_t *)malloc((nb - 1) * N * sizeof(uint32_t));
+        uint32_t *data_M = (uint32_t *)malloc((q - 1) * N * sizeof(uint32_t));
+        fread(data_B, N * (nb - 1), sizeof(uint32_t), file_B);
+        fread(data_M, N * (q - 1), sizeof(uint32_t), file_M);
+
+        for (count_t i = 0; i < M; i++) {
+          forward_data[i] = finite_energy(nb, J, q, H, nv, ne, data_B + (nb - 1) * (drop + i), data_M + (q - 1) * (drop + i));
+        }
+
+        double mean_E = mean(M, forward_data);
+        double squaredMean_E = squared_mean(M, forward_data);
+        double moment2_E = central_moment(M, forward_data, mean_E, 2);
+        double moment4_E = central_moment(M, forward_data, mean_E, 4);
+
+        free(data_B);
+        free(data_M);
+
+        compute_OO(M, forward_plan, forward_data, reverse_plan, reverse_data);
+
+        sprintf(filename_B, "wolff_%lu_E_OO.dat", id);
+
+        FILE *file_E = fopen(filename_B, "wb");
+        fwrite(&M_f, sizeof(double), 1, file_E);
+        fwrite(&mean_E, sizeof(double), 1, file_E);
+        fwrite(&squaredMean_E, sizeof(double), 1, file_E);
+        fwrite(&moment2_E, sizeof(double), 1, file_E);
+        fwrite(&moment4_E, sizeof(double), 1, file_E);
+        fwrite(reverse_data, sizeof(double), length, file_E);
+        fclose(file_E);
+
+        printf("\033[F%lu: Correlation functions for %d steps written.\n", id, M);
+
+        fftw_destroy_plan(forward_plan);
+        fftw_destroy_plan(reverse_plan);
+        fftw_free(forward_data);
+        fftw_free(reverse_data);
+
+      }
+
+      fclose(file_M);
+      fclose(file_B);
+      fclose(file_S);
+
+      free(J);
+      free(H);
+
+      free(filename_S);
+      free(filename_B);
+      free(filename_M);
+
+    } else {
+      char *junk = (char *)malloc(1024 * sizeof(char));
+      fscanf(metadata, "%[^\n]\n", junk); // throw away the rest of the line, we don't need it
+      free(junk);
+
+      char *filename_E = (char *)malloc(128 * sizeof(char));
+      char *filename_F = (char *)malloc(128 * sizeof(char));
+      char *filename_M = (char *)malloc(128 * sizeof(char));
+      char *filename_S = (char *)malloc(128 * sizeof(char));
+
+      sprintf(filename_E, "wolff_%lu_E.dat", id);
+      sprintf(filename_F, "wolff_%lu_F.dat", id);
+      sprintf(filename_M, "wolff_%lu_M.dat", id);
+      sprintf(filename_S, "wolff_%lu_S.dat", id);
+
+      FILE *file_E = fopen(filename_E, "rb");
+      FILE *file_F = fopen(filename_F, "rb");
+      FILE *file_M = fopen(filename_M, "rb");
+      FILE *file_S = fopen(filename_S, "rb");
+
+      fseek(file_S, 0, SEEK_END);
+      unsigned long N = ftell(file_S) / sizeof(uint32_t);
+      fseek(file_S, 0, SEEK_SET);
+
+      if (speedy_drop) {
+        drop = N - pow(2, floor(log(N) / log(2)));
+      } else {
+        if (N % 2 == 1 && drop % 2 == 0) {
+          drop++; // make sure M is even
+        }
+      }
+
+      if (N <= drop) {
+        printf("\033[F%lu: Number of steps %lu is less than %" PRIcount ", nothing done.\n", id, N, drop);
+      } else {
+        int M = N - drop;
+        double M_f = (double)M;
+
+        if (length > M) {
+          length = M;
+        }
+
+        double *forward_data = (double *)fftw_malloc(M * sizeof(double));
+        fftw_plan forward_plan = fftw_plan_r2r_1d(M, forward_data, forward_data, FFTW_R2HC, 0);
+
+        double *reverse_data = (double *)fftw_malloc(M * sizeof(double));
+        fftw_plan reverse_plan = fftw_plan_r2r_1d(M, reverse_data, reverse_data, FFTW_HC2R, 0);
+
+        if (file_S != NULL) {
+          uint32_t *data_S = (uint32_t *)malloc(N * sizeof(uint32_t));
+
+          fread(data_S, sizeof(uint32_t), N, file_S);
+          fclose(file_S);
+
+          for (int i = 0; i < M; i++) {
+            forward_data[i] = (double)data_S[drop + i];
+          }
+          free(data_S);
+
+          double mean_S = mean(M, forward_data);
+          double squaredMean_S = squared_mean(M, forward_data);
+          double moment2_S = central_moment(M, forward_data, mean_S, 2);
+          double moment4_S = central_moment(M, forward_data, mean_S, 4);
+
+          compute_OO(M, forward_plan, forward_data, reverse_plan, reverse_data);
+
+          sprintf(filename_S, "wolff_%lu_S_OO.dat", id);
+          FILE *file_S_new = fopen(filename_S, "wb");
+          fwrite(&M_f, sizeof(double), 1, file_S_new);
+          fwrite(&mean_S, sizeof(double), 1, file_S_new);
+          fwrite(&squaredMean_S, sizeof(double), 1, file_S_new);
+          fwrite(&moment2_S, sizeof(double), 1, file_S_new);
+          fwrite(&moment4_S, sizeof(double), 1, file_S_new);
+          fwrite(reverse_data, sizeof(double), length, file_S_new);
+          fclose(file_S_new);
+        }
+        if (file_F != NULL) {
+          float *data_F = (float *)malloc(N * sizeof(float));
+
+          fread(data_F, sizeof(float), N, file_F);
+          fclose(file_F);
+
+          for (int i = 0; i < M; i++) {
+            forward_data[i] = (double)data_F[drop + i];
+          }
+          free(data_F);
+
+          double mean_F = mean(M, forward_data);
+          double squaredMean_F = squared_mean(M, forward_data);
+          double moment2_F = central_moment(M, forward_data, mean_F, 2);
+          double moment4_F = central_moment(M, forward_data, mean_F, 4);
+
+          compute_OO(M, forward_plan, forward_data, reverse_plan, reverse_data);
+
+          sprintf(filename_F, "wolff_%lu_F_OO.dat", id);
+          FILE *file_F_new = fopen(filename_F, "wb");
+          fwrite(&M_f, sizeof(double), 1, file_F_new);
+          fwrite(&mean_F, sizeof(double), 1, file_F_new);
+          fwrite(&squaredMean_F, sizeof(double), 1, file_F_new);
+          fwrite(&moment2_F, sizeof(double), 1, file_F_new);
+          fwrite(&moment4_F, sizeof(double), 1, file_F_new);
+          fwrite(reverse_data, sizeof(double), length, file_F_new);
+          fclose(file_F_new);
+        }
+        if (file_E != NULL) {
+          float *data_E = (float *)malloc(N * sizeof(float));
+
+          fread(data_E, sizeof(float), N, file_E);
+          fclose(file_E);
+
+          for (int i = 0; i < M; i++) {
+            forward_data[i] = (double)data_E[drop + i];
+          }
+          free(data_E);
+
+          double mean_E = mean(M, forward_data);
+          double squaredMean_E = squared_mean(M, forward_data);
+          double moment2_E = central_moment(M, forward_data, mean_E, 2);
+          double moment4_E = central_moment(M, forward_data, mean_E, 4);
+
+          compute_OO(M, forward_plan, forward_data, reverse_plan, reverse_data);
+
+          sprintf(filename_E, "wolff_%lu_E_OO.dat", id);
+          FILE *file_E_new = fopen(filename_E, "wb");
+          fwrite(&M_f, sizeof(double), 1, file_E_new);
+          fwrite(&mean_E, sizeof(double), 1, file_E_new);
+          fwrite(&squaredMean_E, sizeof(double), 1, file_E_new);
+          fwrite(&moment2_E, sizeof(double), 1, file_E_new);
+          fwrite(&moment4_E, sizeof(double), 1, file_E_new);
+          fwrite(reverse_data, sizeof(double), length, file_E_new);
+          fclose(file_E_new);
+        }
+        if (file_M != NULL) {
+          if (0 == strcmp(model, "PLANAR")) {
+            float *data_M = (float *)malloc(2 * N * sizeof(float));
+            fread(data_M, sizeof(float), 2 * N, file_M);
+            fclose(file_M);
+            for (int i = 0; i < M; i++) {
+              forward_data[i] = (double)sqrt(pow(data_M[2 * drop + 2 * i], 2) + pow(data_M[2 * drop + 2 * i + 1], 2));
+            }
+            free(data_M);
+          } else if (0 == strcmp(model, "HEISENBERG")) {
+            float *data_M = (float *)malloc(3 * N * sizeof(float));
+            fread(data_M, sizeof(float), 3 * N, file_M);
+            fclose(file_M);
+            for (int i = 0; i < M; i++) {
+              forward_data[i] = sqrt(pow(data_M[3 * drop + 3 * i], 2) + pow(data_M[3 * drop + 3 * i + 1], 2) + pow(data_M[3 * drop + 3 * i + 2], 2));
+            }
+            free(data_M);
+          } else if (0 == strcmp(model, "ISING")) {
+            int *data_M = (int *)malloc(N * sizeof(float));
+            fread(data_M, sizeof(int), N, file_M);
+            fclose(file_M);
+            for (int i = 0; i < M; i++) {
+              forward_data[i] = (double)data_M[i];
+            }
+            free(data_M);
+          } else {
+            printf("UNKNOWN MODEL\n");
+            exit(EXIT_FAILURE);
+          }
+
+          double mean_M = mean(M, forward_data);
+          double squaredMean_M = squared_mean(M, forward_data);
+          double moment2_M = central_moment(M, forward_data, mean_M, 2);
+          double moment4_M = central_moment(M, forward_data, mean_M, 4);
+
+          compute_OO(M, forward_plan, forward_data, reverse_plan, reverse_data);
+
+          sprintf(filename_M, "wolff_%lu_M_OO.dat", id);
+          FILE *file_M_new = fopen(filename_M, "wb");
+          fwrite(&M_f, sizeof(double), 1, file_M_new);
+          fwrite(&mean_M, sizeof(double), 1, file_M_new);
+          fwrite(&squaredMean_M, sizeof(double), 1, file_M_new);
+          fwrite(&moment2_M, sizeof(double), 1, file_M_new);
+          fwrite(&moment4_M, sizeof(double), 1, file_M_new);
+          fwrite(reverse_data, sizeof(double), length, file_M_new);
+          fclose(file_M_new);
+        }
+
+        printf("\033[F%lu: Correlation functions for %d steps written.\n", id, M);
+        fftw_destroy_plan(forward_plan);
+        fftw_destroy_plan(reverse_plan);
+        fftw_free(forward_data);
+        fftw_free(reverse_data);
+
+      }
+      free(filename_E);
+      free(filename_S);
+      free(filename_F);
+      free(filename_M);
+    }
+  }
+
+  free(model);
+  fclose(metadata);
+  fftw_cleanup();
+
+  return 0;
+}
+