pattern.c

   1 #define DEBUG
   2 #include <assert.h>
   3 #include <ctype.h>
   4 #include <inttypes.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7
   8 #include "board.h"
   9 #include "debug.h"
  10 #include "pattern.h"
  11 #include "patternsp.h"
  12 #include "pattern3.h"
  13 #include "tactics.h"
  14
  15
  16 struct pattern_config DEFAULT_PATTERN_CONFIG = {
  17         .spat_min = 3, .spat_max = MAX_PATTERN_DIST,
  18         .bdist_max = 4,
  19         .ldist_min = 0, .ldist_max = 256,
  20         .mcsims = 0, /* Unsupported. */
  21 };
  22
  23 struct pattern_config FAST_PATTERN_CONFIG = {
  24         .spat_min = 3, .spat_max = 3,
  25         .bdist_max = -1,
  26         .ldist_min = 0, .ldist_max = 256,
  27         .mcsims = 0,
  28 };
  29
  30 pattern_spec PATTERN_SPEC_MATCHALL = {
  31         [FEAT_PASS] = ~0,
  32         [FEAT_CAPTURE] = ~0,
  33         [FEAT_AESCAPE] = ~0,
  34         [FEAT_SELFATARI] = ~0,
  35         [FEAT_ATARI] = ~0,
  36         [FEAT_BORDER] = ~0,
  37         [FEAT_LDIST] = ~0,
  38         [FEAT_LLDIST] = ~0,
  39         [FEAT_CONTIGUITY] = 0,
  40         [FEAT_SPATIAL] = ~0,
  41         [FEAT_PATTERN3] = 0,
  42         [FEAT_MCOWNER] = ~0,
  43 };
  44
  45 /* !!! Note that in order for ELO playout policy to work correctly, this
  46  * pattern specification MUST exactly match the features matched by the
  47  * BOARD_GAMMA code! You cannot just tinker with this spec freely. */
  48 #define FAST_NO_LADDER 1 /* 1: Don't match ladders in fast playouts */
  49 pattern_spec PATTERN_SPEC_MATCHFAST = {
  50         [FEAT_PASS] = ~0,
  51         [FEAT_CAPTURE] = ~(1<<PF_CAPTURE_ATARIDEF | 1<<PF_CAPTURE_RECAPTURE | FAST_NO_LADDER<<PF_CAPTURE_LADDER | 1<<PF_CAPTURE_KO),
  52         [FEAT_AESCAPE] = ~(FAST_NO_LADDER<<PF_AESCAPE_LADDER),
  53         [FEAT_SELFATARI] = ~(1<<PF_SELFATARI_SMART),
  54         [FEAT_ATARI] = 0,
  55         [FEAT_BORDER] = 0,
  56         [FEAT_LDIST] = 0,
  57         [FEAT_LLDIST] = 0,
  58         [FEAT_CONTIGUITY] = ~0,
  59         [FEAT_SPATIAL] = 0,
  60         [FEAT_PATTERN3] = ~0,
  61         [FEAT_MCOWNER] = 0,
  62 };
  63
  64 static const struct feature_info {
  65         char *name;
  66         int payloads;
  67 } features[FEAT_MAX] = {
  68         [FEAT_PASS] = { .name = "pass", .payloads = 2 },
  69         [FEAT_CAPTURE] = { .name = "capture", .payloads = 64 },
  70         [FEAT_AESCAPE] = { .name = "atariescape", .payloads = 8 },
  71         [FEAT_SELFATARI] = { .name = "selfatari", .payloads = 4 },
  72         [FEAT_ATARI] = { .name = "atari", .payloads = 4 },
  73         [FEAT_BORDER] = { .name = "border", .payloads = -1 },
  74         [FEAT_LDIST] = { .name = "ldist", .payloads = -1 },
  75         [FEAT_LLDIST] = { .name = "lldist", .payloads = -1 },
  76         [FEAT_CONTIGUITY] = { .name = "cont", .payloads = 2 },
  77         [FEAT_SPATIAL] = { .name = "s", .payloads = -1 },
  78         [FEAT_PATTERN3] = { .name = "p", .payloads = 2<<16 },
  79         [FEAT_MCOWNER] = { .name = "mcowner", .payloads = 16 },
  80 };
  81
  82 char *
  83 feature2str(char *str, struct feature *f)
  84 {
  85         return str + sprintf(str + strlen(str), "%s:%d", features[f->id].name, f->payload);
  86 }
  87
  88 char *
  89 str2feature(char *str, struct feature *f)
  90 {
  91         while (isspace(*str)) str++;
  92
  93         int unsigned flen = strcspn(str, ":");
  94         for (unsigned int i = 0; i < sizeof(features)/sizeof(features[0]); i++)
  95                 if (strlen(features[i].name) == flen && !strncmp(features[i].name, str, flen)) {
  96                         f->id = i;
  97                         goto found;
  98                 }
  99         fprintf(stderr, "invalid featurespec: %s[%d]\n", str, flen);
 100         exit(EXIT_FAILURE);
 101
 102 found:
 103         str += flen + 1;
 104         f->payload = strtoull(str, &str, 10);
 105         return str;
 106 }
 107
 108 char *
 109 feature_name(enum feature_id f)
 110 {
 111         return features[f].name;
 112 }
 113
 114 int
 115 feature_payloads(struct pattern_config *pc, enum feature_id f)
 116 {
 117         switch (f) {
 118                 case FEAT_SPATIAL:
 119                         assert(features[f].payloads < 0);
 120                         return pc->spat_dict->nspatials;
 121                 case FEAT_LDIST:
 122                 case FEAT_LLDIST:
 123                         assert(features[f].payloads < 0);
 124                         return pc->ldist_max + 1;
 125                 case FEAT_BORDER:
 126                         assert(features[f].payloads < 0);
 127                         return pc->bdist_max + 1;
 128                 default:
 129                         assert(features[f].payloads > 0);
 130                         return features[f].payloads;
 131         }
 132 }
 133
 134
 135 /* pattern_spec helpers */
 136 #define PS_ANY(F) (ps[FEAT_ ## F] & (1 << 15))
 137 #define PS_PF(F, P) (ps[FEAT_ ## F] & (1 << PF_ ## F ## _ ## P))
 138
 139 static struct feature *
 140 pattern_match_capture(struct pattern_config *pc, pattern_spec ps,
 141                       struct pattern *p, struct feature *f,
 142                       struct board *b, struct move *m)
 143 {
 144         f->id = FEAT_CAPTURE; f->payload = 0;
 145 #ifdef BOARD_TRAITS
 146         if (!trait_at(b, m->coord, m->color).cap)
 147                 return f;
 148         /* Capturable! */
 149         if (!(PS_PF(CAPTURE, LADDER)
 150               || PS_PF(CAPTURE, RECAPTURE)
 151               || PS_PF(CAPTURE, ATARIDEF)
 152               || PS_PF(CAPTURE, KO))) {
 153                 if (PS_PF(CAPTURE, 1STONE))
 154                         f->payload |= (trait_at(b, m->coord, m->color).cap1 == trait_at(b, m->coord, m->color).cap) << PF_CAPTURE_1STONE;
 155                 if (PS_PF(CAPTURE, TRAPPED))
 156                         f->payload |= (!trait_at(b, m->coord, stone_other(m->color)).safe) << PF_CAPTURE_TRAPPED;
 157                 (f++, p->n++);
 158                 return f;
 159         }
 160         /* We need to know details, so we still have to go through
 161          * the neighbors. */
 162 #endif
 163
 164         /* Furthermore, we will now create one feature per capturable
 165          * neighbor. */
 166         /* XXX: I'm not sure if this is really good idea. --pasky */
 167
 168         /* Whether an escape move would be safe for the opponent. */
 169         int captures = 0;
 170         bool can_escape = false;
 171         bool onestone = false, multistone = false;
 172
 173         foreach_neighbor(b, m->coord, {
 174                 if (board_at(b, c) != stone_other(m->color)) {
 175                         if (board_at(b, c) == S_NONE)
 176                                 can_escape = true; // free point
 177                         else if (board_at(b, c) == m->color && board_group_info(b, group_at(b, c)).libs == 1)
 178                                 can_escape = true; // capturable our group
 179                         continue;
 180                 }
 181
 182                 group_t g = group_at(b, c); assert(g);
 183                 if (board_group_info(b, g).libs != 1) {
 184                         can_escape = true;
 185                         continue;
 186                 }
 187
 188                 /* Capture! */
 189                 captures++;
 190
 191                 if (PS_PF(CAPTURE, LADDER))
 192                         f->payload |= is_ladder(b, m->coord, g, true, true) << PF_CAPTURE_LADDER;
 193                 /* TODO: is_ladder() is too conservative in some
 194                  * very obvious situations, look at complete.gtp. */
 195
 196                 /* TODO: PF_CAPTURE_RECAPTURE */
 197
 198                 if (PS_PF(CAPTURE, ATARIDEF))
 199                 foreach_in_group(b, g) {
 200                         foreach_neighbor(b, c, {
 201                                 assert(board_at(b, c) != S_NONE || c == m->coord);
 202                                 if (board_at(b, c) != m->color)
 203                                         continue;
 204                                 group_t g = group_at(b, c);
 205                                 if (!g || board_group_info(b, g).libs != 1)
 206                                         continue;
 207                                 /* A neighboring group of ours is in atari. */
 208                                 f->payload |= 1 << PF_CAPTURE_ATARIDEF;
 209                         });
 210                 } foreach_in_group_end;
 211
 212                 if (PS_PF(CAPTURE, KO)
 213                     && group_is_onestone(b, g)
 214                     && neighbor_count_at(b, m->coord, stone_other(m->color))
 215                        + neighbor_count_at(b, m->coord, S_OFFBOARD) == 4)
 216                         f->payload |= 1 << PF_CAPTURE_KO;
 217
 218                 if (group_is_onestone(b, g))
 219                         onestone = true;
 220                 else
 221                         multistone = true;
 222         });
 223
 224         if (captures > 0) {
 225                 if (PS_PF(CAPTURE, 1STONE))
 226                         f->payload |= (onestone && !multistone) << PF_CAPTURE_1STONE;
 227                 if (PS_PF(CAPTURE, TRAPPED))
 228                         f->payload |= (!can_escape) << PF_CAPTURE_TRAPPED;
 229                 (f++, p->n++);
 230         }
 231         return f;
 232 }
 233
 234 static struct feature *
 235 pattern_match_aescape(struct pattern_config *pc, pattern_spec ps,
 236                       struct pattern *p, struct feature *f,
 237                       struct board *b, struct move *m)
 238 {
 239         f->id = FEAT_AESCAPE; f->payload = 0;
 240 #ifdef BOARD_TRAITS
 241         if (!trait_at(b, m->coord, stone_other(m->color)).cap)
 242                 return f;
 243         /* Opponent can capture something! */
 244         if (!PS_PF(AESCAPE, LADDER)) {
 245                 if (PS_PF(AESCAPE, 1STONE))
 246                         f->payload |= (trait_at(b, m->coord, stone_other(m->color)).cap1 == trait_at(b, m->coord, stone_other(m->color)).cap) << PF_AESCAPE_1STONE;
 247                 if (PS_PF(CAPTURE, TRAPPED))
 248                         f->payload |= (!trait_at(b, m->coord, m->color).safe) << PF_AESCAPE_TRAPPED;
 249                 (f++, p->n++);
 250                 return f;
 251         }
 252         /* We need to know details, so we still have to go through
 253          * the neighbors. */
 254 #endif
 255
 256         /* Find if a neighboring group of ours is in atari, AND that we provide
 257          * a liberty to connect out. XXX: No connect-and-die check. */
 258         group_t in_atari = -1;
 259         bool has_extra_lib = false;
 260         bool onestone = false, multistone = false;
 261
 262         foreach_neighbor(b, m->coord, {
 263                 if (board_at(b, c) != m->color) {
 264                         if (board_at(b, c) == S_NONE)
 265                                 has_extra_lib = true; // free point
 266                         else if (board_at(b, c) == stone_other(m->color) && board_group_info(b, group_at(b, c)).libs == 1)
 267                                 has_extra_lib = true; // capturable enemy group
 268                         continue;
 269                 }
 270                 group_t g = group_at(b, c); assert(g);
 271                 if (board_group_info(b, g).libs != 1) {
 272                         has_extra_lib = true;
 273                         continue;
 274                 }
 275
 276                 /* In atari! */
 277                 in_atari = g;
 278
 279                 if (PS_PF(AESCAPE, LADDER))
 280                         f->payload |= is_ladder(b, m->coord, g, true, true) << PF_AESCAPE_LADDER;
 281                 /* TODO: is_ladder() is too conservative in some
 282                  * very obvious situations, look at complete.gtp. */
 283
 284                 if (group_is_onestone(b, g))
 285                         onestone = true;
 286                 else
 287                         multistone = true;
 288         });
 289
 290         if (in_atari >= 0) {
 291                 if (PS_PF(AESCAPE, 1STONE))
 292                         f->payload |= (onestone && !multistone) << PF_AESCAPE_1STONE;
 293                 if (PS_PF(AESCAPE, TRAPPED))
 294                         f->payload |= (!has_extra_lib) << PF_AESCAPE_TRAPPED;
 295                 (f++, p->n++);
 296         }
 297         return f;
 298 }
 299
 300 static struct feature *
 301 pattern_match_atari(struct pattern_config *pc, pattern_spec ps,
 302                     struct pattern *p, struct feature *f,
 303                     struct board *b, struct move *m)
 304 {
 305         foreach_neighbor(b, m->coord, {
 306                 if (board_at(b, c) != stone_other(m->color))
 307                         continue;
 308                 group_t g = group_at(b, c);
 309                 if (!g || board_group_info(b, g).libs != 2)
 310                         continue;
 311
 312                 /* Can atari! */
 313                 f->id = FEAT_ATARI; f->payload = 0;
 314
 315                 if (PS_PF(ATARI, LADDER)) {
 316                         /* Opponent will escape by the other lib. */
 317                         coord_t lib = board_group_info(b, g).lib[0];
 318                         if (lib == m->coord) lib = board_group_info(b, g).lib[1];
 319                         /* TODO: is_ladder() is too conservative in some
 320                          * very obvious situations, look at complete.gtp. */
 321                         f->payload |= is_ladder(b, lib, g, true, true) << PF_ATARI_LADDER;
 322                 }
 323
 324                 if (PS_PF(ATARI, KO) && !is_pass(b->ko.coord))
 325                         f->payload |= 1 << PF_ATARI_KO;
 326
 327                 (f++, p->n++);
 328         });
 329         return f;
 330 }
 331
 332 #ifndef BOARD_SPATHASH
 333 #undef BOARD_SPATHASH_MAXD
 334 #define BOARD_SPATHASH_MAXD 1
 335 #endif
 336
 337 /* Match spatial features that are too distant to be pre-matched
 338  * incrementally. */
 339 struct feature *
 340 pattern_match_spatial_outer(struct pattern_config *pc, pattern_spec ps,
 341                             struct pattern *p, struct feature *f,
 342                             struct board *b, struct move *m, hash_t h)
 343 {
 344         /* We record all spatial patterns black-to-play; simply
 345          * reverse all colors if we are white-to-play. */
 346         static enum stone bt_black[4] = { S_NONE, S_BLACK, S_WHITE, S_OFFBOARD };
 347         static enum stone bt_white[4] = { S_NONE, S_WHITE, S_BLACK, S_OFFBOARD };
 348         enum stone (*bt)[4] = m->color == S_WHITE ? &bt_white : &bt_black;
 349
 350         for (int d = BOARD_SPATHASH_MAXD + 1; d <= pc->spat_max; d++) {
 351                 /* Recompute missing outer circles:
 352                  * Go through all points in given distance. */
 353                 for (int j = ptind[d]; j < ptind[d + 1]; j++) {
 354                         ptcoords_at(x, y, m->coord, b, j);
 355                         h ^= pthashes[0][j][(*bt)[board_atxy(b, x, y)]];
 356                 }
 357                 if (d < pc->spat_min)
 358                         continue;
 359                 /* Record spatial feature, one per distance. */
 360                 int sid = spatial_dict_get(pc->spat_dict, d, h & spatial_hash_mask);
 361                 if (sid > 0) {
 362                         f->id = FEAT_SPATIAL;
 363                         f->payload = sid;
 364                         (f++, p->n++);
 365                 } /* else not found, ignore */
 366         }
 367         return f;
 368 }
 369
 370 struct feature *
 371 pattern_match_spatial(struct pattern_config *pc, pattern_spec ps,
 372                       struct pattern *p, struct feature *f,
 373                       struct board *b, struct move *m)
 374 {
 375         /* XXX: This is partially duplicated from spatial_from_board(), but
 376          * we build a hash instead of spatial record. */
 377
 378         assert(pc->spat_min > 0);
 379
 380         hash_t h = pthashes[0][0][S_NONE];
 381 #ifdef BOARD_SPATHASH
 382         bool w_to_play = m->color == S_WHITE;
 383         for (int d = 2; d <= BOARD_SPATHASH_MAXD; d++) {
 384                 /* Reuse all incrementally matched data. */
 385                 h ^= b->spathash[m->coord][d - 1][w_to_play];
 386                 if (d < pc->spat_min)
 387                         continue;
 388                 /* Record spatial feature, one per distance. */
 389                 int sid = spatial_dict_get(pc->spat_dict, d, h & spatial_hash_mask);
 390                 if (sid > 0) {
 391                         f->id = FEAT_SPATIAL;
 392                         f->payload = sid;
 393                         (f++, p->n++);
 394                 } /* else not found, ignore */
 395         }
 396 #else
 397         assert(BOARD_SPATHASH_MAXD < 2);
 398 #endif
 399         if (unlikely(pc->spat_max > BOARD_SPATHASH_MAXD))
 400                 f = pattern_match_spatial_outer(pc, ps, p, f, b, m, h);
 401         return f;
 402 }
 403
 404
 405 void
 406 pattern_match(struct pattern_config *pc, pattern_spec ps,
 407               struct pattern *p, struct board *b, struct move *m)
 408 {
 409         p->n = 0;
 410         struct feature *f = &p->f[0];
 411
 412         /* TODO: We should match pretty much all of these features
 413          * incrementally. */
 414
 415         if (is_pass(m->coord)) {
 416                 if (PS_ANY(PASS)) {
 417                         f->id = FEAT_PASS; f->payload = 0;
 418                         if (PS_PF(PASS, LASTPASS))
 419                                 f->payload |= (b->moves > 0 && is_pass(b->last_move.coord))
 420                                                 << PF_PASS_LASTPASS;
 421                         p->n++;
 422                 }
 423                 return;
 424         }
 425
 426         if (PS_ANY(CAPTURE)) {
 427                 f = pattern_match_capture(pc, ps, p, f, b, m);
 428         }
 429
 430         if (PS_ANY(AESCAPE)) {
 431                 f = pattern_match_aescape(pc, ps, p, f, b, m);
 432         }
 433
 434         if (PS_ANY(SELFATARI)) {
 435                 bool simple = false;
 436                 if (PS_PF(SELFATARI, STUPID)) {
 437 #ifdef BOARD_TRAITS
 438                         if (!b->precise_selfatari)
 439                                 simple = !trait_at(b, m->coord, m->color).safe;
 440                         else
 441 #endif
 442                         simple = !board_safe_to_play(b, m->coord, m->color);
 443                 }
 444                 bool thorough = false;
 445                 if (PS_PF(SELFATARI, SMART)) {
 446 #ifdef BOARD_TRAITS
 447                         if (b->precise_selfatari)
 448                                 thorough = !trait_at(b, m->coord, m->color).safe;
 449                         else
 450 #endif
 451                         thorough = is_bad_selfatari(b, m->color, m->coord);
 452                 }
 453                 if (simple || thorough) {
 454                         f->id = FEAT_SELFATARI;
 455                         f->payload = simple << PF_SELFATARI_STUPID;
 456                         f->payload |= thorough << PF_SELFATARI_SMART;
 457                         (f++, p->n++);
 458                 }
 459         }
 460
 461         if (PS_ANY(ATARI)) {
 462                 f = pattern_match_atari(pc, ps, p, f, b, m);
 463         }
 464
 465         if (PS_ANY(BORDER)) {
 466                 int bdist = coord_edge_distance(m->coord, b);
 467                 if (bdist <= pc->bdist_max) {
 468                         f->id = FEAT_BORDER;
 469                         f->payload = bdist;
 470                         (f++, p->n++);
 471                 }
 472         }
 473
 474         if (PS_ANY(CONTIGUITY) && !is_pass(b->last_move.coord)
 475             && coord_is_8adjecent(m->coord, b->last_move.coord, b)) {
 476                 f->id = FEAT_CONTIGUITY;
 477                 f->payload = 1;
 478                 (f++, p->n++);
 479         }
 480
 481         if (PS_ANY(LDIST) && pc->ldist_max > 0 && !is_pass(b->last_move.coord)) {
 482                 int ldist = coord_gridcular_distance(m->coord, b->last_move.coord, b);
 483                 if (pc->ldist_min <= ldist && ldist <= pc->ldist_max) {
 484                         f->id = FEAT_LDIST;
 485                         f->payload = ldist;
 486                         (f++, p->n++);
 487                 }
 488         }
 489
 490         if (PS_ANY(LLDIST) && pc->ldist_max > 0 && !is_pass(b->last_move2.coord)) {
 491                 int lldist = coord_gridcular_distance(m->coord, b->last_move2.coord, b);
 492                 if (pc->ldist_min <= lldist && lldist <= pc->ldist_max) {
 493                         f->id = FEAT_LLDIST;
 494                         f->payload = lldist;
 495                         (f++, p->n++);
 496                 }
 497         }
 498
 499         if (PS_ANY(SPATIAL) && pc->spat_max > 0 && pc->spat_dict) {
 500                 f = pattern_match_spatial(pc, ps, p, f, b, m);
 501         }
 502
 503         if (PS_ANY(PATTERN3) && !is_pass(m->coord)) {
 504 #ifdef BOARD_PAT3
 505                 hash3_t pat = b->pat3[m->coord];
 506 #else
 507                 hash3_t pat = pattern3_hash(b, m->coord);
 508 #endif
 509                 if (m->color == S_WHITE) {
 510                         /* We work with the pattern3s as black-to-play. */
 511                         pat = pattern3_reverse(pat);
 512                 }
 513                 f->id = FEAT_PATTERN3;
 514                 f->payload = pat;
 515                 (f++, p->n++);
 516         }
 517
 518         /* FEAT_MCOWNER: TODO */
 519         assert(!pc->mcsims);
 520 }
 521
 522 char *
 523 pattern2str(char *str, struct pattern *p)
 524 {
 525         str = stpcpy(str, "(");
 526         for (int i = 0; i < p->n; i++) {
 527                 if (i > 0) str = stpcpy(str, " ");
 528                 str = feature2str(str, &p->f[i]);
 529         }
 530         str = stpcpy(str, ")");
 531         return str;
 532 }
 533
 534
 535
 536 /*** Features gamma set */
 537
 538 static void
 539 features_gamma_load(struct features_gamma *fg, const char *filename)
 540 {
 541         FILE *f = fopen(filename, "r");
 542         if (!f) return;
 543         char buf[256];
 544         while (fgets(buf, 256, f)) {
 545                 char *bufp = buf;
 546                 struct feature f;
 547                 bufp = str2feature(bufp, &f);
 548                 while (isspace(*bufp)) bufp++;
 549                 double gamma = strtod(bufp, &bufp);
 550                 /* Record feature's gamma. */
 551                 feature_gamma(fg, &f, &gamma);
 552                 /* In case of 3x3 patterns, record gamma also
 553                  * for all rotations and transpositions. */
 554                 if (f.id == FEAT_PATTERN3) {
 555                         hash3_t transp[8];
 556                         pattern3_transpose(f.payload, &transp);
 557                         for (int i = 1; i < 8; i++) {
 558                                 f.payload = transp[i];
 559                                 feature_gamma(fg, &f, &gamma);
 560                         }
 561                         f.payload = transp[0];
 562                 }
 563         }
 564         fclose(f);
 565 }
 566
 567 const char *features_gamma_filename = "patterns.gamma";
 568
 569 struct features_gamma *
 570 features_gamma_init(struct pattern_config *pc, const char *file)
 571 {
 572         struct features_gamma *fg = calloc2(1, sizeof(*fg));
 573         fg->pc = pc;
 574         for (int i = 0; i < FEAT_MAX; i++) {
 575                 int n = feature_payloads(pc, i);
 576                 fg->gamma[i] = malloc2(n * sizeof(fg->gamma[0][0]));
 577                 for (int j = 0; j < n; j++) {
 578                         fg->gamma[i][j] = 1.0f;
 579                 }
 580         }
 581         features_gamma_load(fg, file ? file : features_gamma_filename);
 582         return fg;
 583 }
 584
 585 void
 586 features_gamma_done(struct features_gamma *fg)
 587 {
 588         for (int i = 0; i < FEAT_MAX; i++)
 589                 free(fg->gamma[i]);
 590         free(fg);
 591 }