uct/dynkomi.c

   1 #define DEBUG
   2 #include <assert.h>
   3 #include <math.h>
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7
   8 #include "board.h"
   9 #include "debug.h"
  10 #include "tactics/util.h"
  11 #include "uct/dynkomi.h"
  12 #include "uct/internal.h"
  13 #include "uct/tree.h"
  14
  15
  16 static void
  17 generic_done(struct uct_dynkomi *d)
  18 {
  19         if (d->data) free(d->data);
  20         free(d);
  21 }
  22
  23
  24 /* NONE dynkomi strategy - never fiddle with komi values. */
  25
  26 struct uct_dynkomi *
  27 uct_dynkomi_init_none(struct uct *u, char *arg, struct board *b)
  28 {
  29         struct uct_dynkomi *d = calloc2(1, sizeof(*d));
  30         d->uct = u;
  31         d->permove = NULL;
  32         d->persim = NULL;
  33         d->done = generic_done;
  34         d->data = NULL;
  35
  36         if (arg) {
  37                 fprintf(stderr, "uct: Dynkomi method none accepts no arguments\n");
  38                 exit(1);
  39         }
  40
  41         return d;
  42 }
  43
  44
  45 /* LINEAR dynkomi strategy - Linearly Decreasing Handicap Compensation. */
  46 /* At move 0, we impose extra komi of handicap_count*handicap_value, then
  47  * we linearly decrease this extra komi throughout the game down to 0
  48  * at @moves moves. Towards the end of the game the linear compensation
  49  * becomes zero but we increase the extra komi when winning big. This reduces
  50  * the number of point-wasting moves and makes the game more enjoyable for humans. */
  51
  52 struct dynkomi_linear {
  53         int handicap_value[S_MAX];
  54         int moves[S_MAX];
  55         bool rootbased;
  56         /* Increase the extra komi if my win ratio  > green_zone but always
  57          * keep extra_komi <= komi_ratchet. komi_ratchet starts infinite but decreases
  58          * when we give too much extra komi and this puts us back < orange_zone.
  59          * This is meant only to increase the territory margin when playing against
  60          * weaker opponents. We never take negative komi when losing. The ratchet helps
  61          * avoiding oscillations and keeping us above orange_zone.
  62          * To disable the adaptive phase, set green_zone=2. */
  63         floating_t komi_ratchet;
  64         floating_t green_zone;
  65         floating_t orange_zone;
  66         floating_t drop_step;
  67 };
  68
  69 static floating_t
  70 linear_permove(struct uct_dynkomi *d, struct board *b, struct tree *tree)
  71 {
  72         struct dynkomi_linear *l = d->data;
  73         enum stone color = d->uct->pondering ? tree->root_color : stone_other(tree->root_color);
  74         int lmoves = l->moves[color];
  75         floating_t extra_komi;
  76
  77         if (b->moves < lmoves) {
  78                 floating_t base_komi = board_effective_handicap(b, l->handicap_value[color]);
  79                 extra_komi = base_komi * (lmoves - b->moves) / lmoves;
  80                 return extra_komi;
  81         } else {
  82                 extra_komi = floor(tree->extra_komi);
  83         }
  84
  85         /* Do not take decisions on unstable value. */
  86         if (tree->root->u.playouts < GJ_MINGAMES) return extra_komi;
  87
  88         floating_t my_value = tree_node_get_value(tree, 1, tree->root->u.value);
  89         /*  We normalize komi as in komi_by_value(), > 0 when winning. */
  90         extra_komi = komi_by_color(extra_komi, color);
  91         if (extra_komi < 0 && DEBUGL(3))
  92                 fprintf(stderr, "XXX: extra_komi %.3f < 0 (color %s tree ek %.3f)\n", extra_komi, stone2str(color), tree->extra_komi);
  93         // assert(extra_komi >= 0);
  94         floating_t orig_komi = extra_komi;
  95
  96         if (my_value < 0.5 && l->komi_ratchet > 0 && l->komi_ratchet != INFINITY) {
  97                 if (DEBUGL(0))
  98                         fprintf(stderr, "losing %f extra komi %.1f ratchet %.1f -> 0\n",
  99                                 my_value, extra_komi, l->komi_ratchet);
 100                 /* Disable dynkomi completely, too dangerous in this game. */
 101                 extra_komi = l->komi_ratchet = 0;
 102
 103         } else if (my_value < l->orange_zone && extra_komi > 0) {
 104                 extra_komi = l->komi_ratchet  = fmax(extra_komi - l->drop_step, 0.0);
 105                 if (extra_komi != orig_komi && DEBUGL(3))
 106                         fprintf(stderr, "dropping to %f, extra komi %.1f -> ratchet %.1f\n",
 107                                 my_value, orig_komi, extra_komi);
 108
 109         } else if (my_value > l->green_zone && extra_komi + 1 <= l->komi_ratchet) {
 110                 extra_komi += 1;
 111                 if (extra_komi != orig_komi && DEBUGL(3))
 112                         fprintf(stderr, "winning %f extra_komi %.1f -> %.1f, ratchet %.1f\n",
 113                                 my_value, orig_komi, extra_komi, l->komi_ratchet);
 114         }
 115         return komi_by_color(extra_komi, color);
 116 }
 117
 118 static floating_t
 119 linear_persim(struct uct_dynkomi *d, struct board *b, struct tree *tree, struct tree_node *node)
 120 {
 121         struct dynkomi_linear *l = d->data;
 122         if (l->rootbased)
 123                 return tree->extra_komi;
 124         /* We don't reuse computed value from tree->extra_komi,
 125          * since we want to use value correct for this node depth.
 126          * This also means the values will stay correct after
 127          * node promotion. */
 128         return linear_permove(d, b, tree);
 129 }
 130
 131 struct uct_dynkomi *
 132 uct_dynkomi_init_linear(struct uct *u, char *arg, struct board *b)
 133 {
 134         struct uct_dynkomi *d = calloc2(1, sizeof(*d));
 135         d->uct = u;
 136         d->permove = linear_permove;
 137         d->persim = linear_persim;
 138         d->done = generic_done;
 139
 140         struct dynkomi_linear *l = calloc2(1, sizeof(*l));
 141         d->data = l;
 142
 143         /* Force white to feel behind and try harder, but not to the
 144          * point of resigning immediately in high handicap games.
 145          * By move 100 white should still be behind but should have
 146          * caught up enough to avoid resigning. */
 147         if (board_large(b)) {
 148                 l->moves[S_BLACK] = 100;
 149                 l->moves[S_WHITE] = 50;
 150         }
 151         /* The real value of one stone is twice the komi so about 15 points.
 152          * But use a lower value to avoid being too pessimistic as black
 153          * or too optimistic as white. */
 154         l->handicap_value[S_BLACK] = 8;
 155         l->handicap_value[S_WHITE] = 1;
 156
 157         l->komi_ratchet = INFINITY;
 158         l->green_zone = 0.85;
 159         l->orange_zone = 0.8;
 160         l->drop_step = 4.0;
 161
 162         if (arg) {
 163                 char *optspec, *next = arg;
 164                 while (*next) {
 165                         optspec = next;
 166                         next += strcspn(next, ":");
 167                         if (*next) { *next++ = 0; } else { *next = 0; }
 168
 169                         char *optname = optspec;
 170                         char *optval = strchr(optspec, '=');
 171                         if (optval) *optval++ = 0;
 172
 173                         if (!strcasecmp(optname, "moves") && optval) {
 174                                 /* Dynamic komi in handicap game; linearly
 175                                  * decreases to basic settings until move
 176                                  * #optval. moves=blackmoves%whitemoves */
 177                                 for (int i = S_BLACK; *optval && i <= S_WHITE; i++) {
 178                                         l->moves[i] = atoi(optval);
 179                                         optval += strcspn(optval, "%");
 180                                         if (*optval) optval++;
 181                                 }
 182                         } else if (!strcasecmp(optname, "handicap_value") && optval) {
 183                                 /* Point value of single handicap stone,
 184                                  * for dynkomi computation. */
 185                                 for (int i = S_BLACK; *optval && i <= S_WHITE; i++) {
 186                                         l->handicap_value[i] = atoi(optval);
 187                                         optval += strcspn(optval, "%");
 188                                         if (*optval) optval++;
 189                                 }
 190                         } else if (!strcasecmp(optname, "rootbased")) {
 191                                 /* If set, the extra komi applied will be
 192                                  * the same for all simulations within a move,
 193                                  * instead of being same for all simulations
 194                                  * within the tree node. */
 195                                 l->rootbased = !optval || atoi(optval);
 196                         } else if (!strcasecmp(optname, "green_zone") && optval) {
 197                                 /* Increase komi when win ratio is above green_zone */
 198                                 l->green_zone = atof(optval);
 199                         } else if (!strcasecmp(optname, "orange_zone") && optval) {
 200                                 /* Decrease komi when > 0 and win ratio is below orange_zone */
 201                                 l->orange_zone = atof(optval);
 202                         } else if (!strcasecmp(optname, "drop_step") && optval) {
 203                                 /* Decrease komi by drop_step points */
 204                                 l->drop_step = atof(optval);
 205                         } else {
 206                                 fprintf(stderr, "uct: Invalid dynkomi argument %s or missing value\n", optname);
 207                                 exit(1);
 208                         }
 209                 }
 210         }
 211
 212         return d;
 213 }
 214
 215
 216 /* ADAPTIVE dynkomi strategy - Adaptive Situational Compensation */
 217 /* We adapt the komi based on current situation:
 218  * (i) score-based: We maintain the average score outcome of our
 219  * games and adjust the komi by a fractional step towards the expected
 220  * score;
 221  * (ii) value-based: While winrate is above given threshold, adjust
 222  * the komi by a fixed step in the appropriate direction.
 223  * These adjustments can be
 224  * (a) Move-stepped, new extra komi value is always set only at the
 225  * beginning of the tree search for next move;
 226  * (b) Continuous, new extra komi value is periodically re-determined
 227  * and adjusted throughout a single tree search. */
 228
 229 struct dynkomi_adaptive {
 230         /* Do not take measured average score into regard for
 231          * first @lead_moves - the variance is just too much.
 232          * (Instead, we consider the handicap-based komi provided
 233          * by linear dynkomi.) */
 234         int lead_moves;
 235         /* Maximum komi to pretend the opponent to give. */
 236         floating_t max_losing_komi;
 237         /* Game portion at which losing komi is not allowed anymore. */
 238         floating_t losing_komi_stop;
 239         /* Turn off dynkomi at the (perceived) closing of the game
 240          * (last few moves). */
 241         bool no_komi_at_game_end;
 242         /* Alternative game portion determination. */
 243         bool adapt_aport;
 244         floating_t (*indicator)(struct uct_dynkomi *d, struct board *b, struct tree *tree, enum stone color);
 245
 246         /* Value-based adaptation. */
 247         floating_t zone_red, zone_green;
 248         int score_step;
 249         floating_t score_step_byavg; // use portion of average score as increment
 250         bool use_komi_ratchet;
 251         bool losing_komi_ratchet; // ratchet even losing komi
 252         int komi_ratchet_maxage;
 253         // runtime, not configuration:
 254         int komi_ratchet_age;
 255         floating_t komi_ratchet;
 256
 257         /* Score-based adaptation. */
 258         floating_t (*adapter)(struct uct_dynkomi *d, struct board *b);
 259         floating_t adapt_base; // [0,1)
 260         /* Sigmoid adaptation rate parameter; see below for details. */
 261         floating_t adapt_phase; // [0,1]
 262         floating_t adapt_rate; // [1,infty)
 263         /* Linear adaptation rate parameter. */
 264         int adapt_moves;
 265         floating_t adapt_dir; // [-1,1]
 266 };
 267 #define TRUSTWORTHY_KOMI_PLAYOUTS 200
 268
 269 static floating_t
 270 board_game_portion(struct dynkomi_adaptive *a, struct board *b)
 271 {
 272         if (!a->adapt_aport) {
 273                 int total_moves = b->moves + 2 * board_estimated_moves_left(b);
 274                 return (floating_t) b->moves / total_moves;
 275         } else {
 276                 int brsize = board_size(b) - 2;
 277                 return 1.0 - (floating_t) b->flen / (brsize * brsize);
 278         }
 279 }
 280
 281 static floating_t
 282 adapter_sigmoid(struct uct_dynkomi *d, struct board *b)
 283 {
 284         struct dynkomi_adaptive *a = d->data;
 285         /* Figure out how much to adjust the komi based on the game
 286          * stage. The adaptation rate is 0 at the beginning,
 287          * at game stage a->adapt_phase crosses though 0.5 and
 288          * approaches 1 at the game end; the slope is controlled
 289          * by a->adapt_rate. */
 290         floating_t game_portion = board_game_portion(a, b);
 291         floating_t l = game_portion - a->adapt_phase;
 292         return 1.0 / (1.0 + exp(-a->adapt_rate * l));
 293 }
 294
 295 static floating_t
 296 adapter_linear(struct uct_dynkomi *d, struct board *b)
 297 {
 298         struct dynkomi_adaptive *a = d->data;
 299         /* Figure out how much to adjust the komi based on the game
 300          * stage. We just linearly increase/decrease the adaptation
 301          * rate for first N moves. */
 302         if (b->moves > a->adapt_moves)
 303                 return 0;
 304         if (a->adapt_dir < 0)
 305                 return 1 - (- a->adapt_dir) * b->moves / a->adapt_moves;
 306         else
 307                 return a->adapt_dir * b->moves / a->adapt_moves;
 308 }
 309
 310 static floating_t
 311 komi_by_score(struct uct_dynkomi *d, struct board *b, struct tree *tree, enum stone color)
 312 {
 313         struct dynkomi_adaptive *a = d->data;
 314         if (d->score.playouts < TRUSTWORTHY_KOMI_PLAYOUTS)
 315                 return tree->extra_komi;
 316
 317         struct move_stats score = d->score;
 318         /* Almost-reset tree->score to gather fresh stats. */
 319         d->score.playouts = 1;
 320
 321         /* Look at average score and push extra_komi in that direction. */
 322         floating_t p = a->adapter(d, b);
 323         p = a->adapt_base + p * (1 - a->adapt_base);
 324         if (p > 0.9) p = 0.9; // don't get too eager!
 325         floating_t extra_komi = tree->extra_komi + p * score.value;
 326         if (DEBUGL(3))
 327                 fprintf(stderr, "mC += %f * %f\n", p, score.value);
 328         return extra_komi;
 329 }
 330
 331 static floating_t
 332 komi_by_value(struct uct_dynkomi *d, struct board *b, struct tree *tree, enum stone color)
 333 {
 334         struct dynkomi_adaptive *a = d->data;
 335         if (d->value.playouts < TRUSTWORTHY_KOMI_PLAYOUTS)
 336                 return tree->extra_komi;
 337
 338         struct move_stats value = d->value;
 339         /* Almost-reset tree->value to gather fresh stats. */
 340         d->value.playouts = 1;
 341         /* Correct color POV. */
 342         if (color == S_WHITE)
 343                 value.value = 1 - value.value;
 344
 345         /* We have three "value zones":
 346          * red zone | yellow zone | green zone
 347          *        ~45%           ~60%
 348          * red zone: reduce komi
 349          * yellow zone: do not touch komi
 350          * green zone: enlage komi.
 351          *
 352          * Also, at some point komi will be tuned in such way
 353          * that it will be in green zone but increasing it will
 354          * be unfeasible. Thus, we have a _ratchet_ - we will
 355          * remember the last komi that has put us into the
 356          * red zone, and not use it or go over it. We use the
 357          * ratchet only when giving extra komi, we always want
 358          * to try to reduce extra komi we take.
 359          *
 360          * TODO: Make the ratchet expire after a while. */
 361
 362         /* We use komi_by_color() first to normalize komi
 363          * additions/subtractions, then apply it again on
 364          * return value to restore original komi parity. */
 365         /* Positive extra_komi means that we are _giving_
 366          * komi (winning), negative extra_komi is _taking_
 367          * komi (losing). */
 368         floating_t extra_komi = komi_by_color(tree->extra_komi, color);
 369         int score_step_red = -a->score_step;
 370         int score_step_green = a->score_step;
 371
 372         if (a->score_step_byavg != 0) {
 373                 struct move_stats score = d->score;
 374                 /* Almost-reset tree->score to gather fresh stats. */
 375                 d->score.playouts = 1;
 376                 /* Correct color POV. */
 377                 if (color == S_WHITE)
 378                         score.value = - score.value;
 379                 if (score.value > 0)
 380                         score_step_green = round(score.value * a->score_step_byavg);
 381                 else
 382                         score_step_red = round(-score.value * a->score_step_byavg);
 383                 if (score_step_green < 0 || score_step_red > 0) {
 384                         /* The steps are in bad direction - keep still. */
 385                         return komi_by_color(extra_komi, color);
 386                 }
 387         }
 388
 389         /* Wear out the ratchet. */
 390         if (a->use_komi_ratchet && a->komi_ratchet_maxage > 0) {
 391                 a->komi_ratchet_age += value.playouts;
 392                 if (a->komi_ratchet_age > a->komi_ratchet_maxage) {
 393                         a->komi_ratchet = 1000;
 394                         a->komi_ratchet_age = 0;
 395                 }
 396         }
 397
 398         if (value.value < a->zone_red) {
 399                 /* Red zone. Take extra komi. */
 400                 if (DEBUGL(3))
 401                         fprintf(stderr, "[red] %f, step %d | komi ratchet %f age %d/%d -> %f\n",
 402                                 value.value, score_step_red, a->komi_ratchet, a->komi_ratchet_age, a->komi_ratchet_maxage, extra_komi);
 403                 if (a->losing_komi_ratchet || extra_komi > 0) {
 404                         a->komi_ratchet = extra_komi;
 405                         a->komi_ratchet_age = 0;
 406                 }
 407                 extra_komi += score_step_red;
 408                 return komi_by_color(extra_komi, color);
 409
 410         } else if (value.value < a->zone_green) {
 411                 /* Yellow zone, do nothing. */
 412                 return komi_by_color(extra_komi, color);
 413
 414         } else {
 415                 /* Green zone. Give extra komi. */
 416                 if (DEBUGL(3))
 417                         fprintf(stderr, "[green] %f, step %d | komi ratchet %f age %d/%d\n",
 418                                 value.value, score_step_green, a->komi_ratchet, a->komi_ratchet_age, a->komi_ratchet_maxage);
 419                 extra_komi += score_step_green;
 420                 if (a->use_komi_ratchet && extra_komi >= a->komi_ratchet)
 421                         extra_komi = a->komi_ratchet - 1;
 422                 return komi_by_color(extra_komi, color);
 423         }
 424 }
 425
 426 static floating_t
 427 bounded_komi(struct dynkomi_adaptive *a, struct board *b,
 428              enum stone color, floating_t komi, floating_t max_losing_komi)
 429 {
 430         /* At the end of game, disallow losing komi. */
 431         if (komi_by_color(komi, color) < 0
 432             && board_game_portion(a, b) > a->losing_komi_stop)
 433                 return 0;
 434
 435         /* Get lower bound on komi we take so that we don't underperform
 436          * too much. */
 437         floating_t min_komi = komi_by_color(- max_losing_komi, color);
 438
 439         if (komi_by_color(komi - min_komi, color) > 0)
 440                 return komi;
 441         else
 442                 return min_komi;
 443 }
 444
 445 static floating_t
 446 adaptive_permove(struct uct_dynkomi *d, struct board *b, struct tree *tree)
 447 {
 448         struct dynkomi_adaptive *a = d->data;
 449         enum stone color = stone_other(tree->root_color);
 450
 451         /* We do not use extra komi at the game end - we are not
 452          * to fool ourselves at this point. */
 453         if (a->no_komi_at_game_end && board_estimated_moves_left(b) <= MIN_MOVES_LEFT) {
 454                 tree->use_extra_komi = false;
 455                 return 0;
 456         }
 457
 458         if (DEBUGL(4))
 459                 fprintf(stderr, "m %d/%d ekomi %f permove %f/%d\n",
 460                         b->moves, a->lead_moves, tree->extra_komi,
 461                         d->score.value, d->score.playouts);
 462
 463         if (b->moves <= a->lead_moves)
 464                 return bounded_komi(a, b, color,
 465                                     board_effective_handicap(b, 7 /* XXX */),
 466                                     a->max_losing_komi);
 467
 468         floating_t komi = a->indicator(d, b, tree, color);
 469         if (DEBUGL(4))
 470                 fprintf(stderr, "dynkomi: %f -> %f\n", tree->extra_komi, komi);
 471         return bounded_komi(a, b, color, komi, a->max_losing_komi);
 472 }
 473
 474 static floating_t
 475 adaptive_persim(struct uct_dynkomi *d, struct board *b, struct tree *tree, struct tree_node *node)
 476 {
 477         return tree->extra_komi;
 478 }
 479
 480 struct uct_dynkomi *
 481 uct_dynkomi_init_adaptive(struct uct *u, char *arg, struct board *b)
 482 {
 483         struct uct_dynkomi *d = calloc2(1, sizeof(*d));
 484         d->uct = u;
 485         d->permove = adaptive_permove;
 486         d->persim = adaptive_persim;
 487         d->done = generic_done;
 488
 489         struct dynkomi_adaptive *a = calloc2(1, sizeof(*a));
 490         d->data = a;
 491
 492         a->lead_moves = board_large(b) ? 20 : 4; // XXX
 493         a->max_losing_komi = 30;
 494         a->losing_komi_stop = 1.0f;
 495         a->no_komi_at_game_end = true;
 496         a->indicator = komi_by_value;
 497
 498         a->adapter = adapter_sigmoid;
 499         a->adapt_rate = -18;
 500         a->adapt_phase = 0.65;
 501         a->adapt_moves = 200;
 502         a->adapt_dir = -0.5;
 503
 504         a->zone_red = 0.45;
 505         a->zone_green = 0.50;
 506         a->score_step = 1;
 507         a->use_komi_ratchet = true;
 508         a->komi_ratchet_maxage = 0;
 509         a->komi_ratchet = 1000;
 510
 511         if (arg) {
 512                 char *optspec, *next = arg;
 513                 while (*next) {
 514                         optspec = next;
 515                         next += strcspn(next, ":");
 516                         if (*next) { *next++ = 0; } else { *next = 0; }
 517
 518                         char *optname = optspec;
 519                         char *optval = strchr(optspec, '=');
 520                         if (optval) *optval++ = 0;
 521
 522                         if (!strcasecmp(optname, "lead_moves") && optval) {
 523                                 /* Do not adjust komi adaptively for first
 524                                  * N moves. */
 525                                 a->lead_moves = atoi(optval);
 526                         } else if (!strcasecmp(optname, "max_losing_komi") && optval) {
 527                                 a->max_losing_komi = atof(optval);
 528                         } else if (!strcasecmp(optname, "losing_komi_stop") && optval) {
 529                                 a->losing_komi_stop = atof(optval);
 530                         } else if (!strcasecmp(optname, "no_komi_at_game_end")) {
 531                                 a->no_komi_at_game_end = !optval || atoi(optval);
 532                         } else if (!strcasecmp(optname, "indicator")) {
 533                                 /* Adaptatation indicator - how to decide
 534                                  * the adaptation rate and direction. */
 535                                 if (!strcasecmp(optval, "value")) {
 536                                         /* Winrate w/ komi so far. */
 537                                         a->indicator = komi_by_value;
 538                                 } else if (!strcasecmp(optval, "score")) {
 539                                         /* Expected score w/ current komi. */
 540                                         a->indicator = komi_by_score;
 541                                 } else {
 542                                         fprintf(stderr, "UCT: Invalid indicator %s\n", optval);
 543                                         exit(1);
 544                                 }
 545
 546                                 /* value indicator settings */
 547                         } else if (!strcasecmp(optname, "zone_red") && optval) {
 548                                 a->zone_red = atof(optval);
 549                         } else if (!strcasecmp(optname, "zone_green") && optval) {
 550                                 a->zone_green = atof(optval);
 551                         } else if (!strcasecmp(optname, "score_step") && optval) {
 552                                 a->score_step = atoi(optval);
 553                         } else if (!strcasecmp(optname, "score_step_byavg") && optval) {
 554                                 a->score_step_byavg = atof(optval);
 555                         } else if (!strcasecmp(optname, "use_komi_ratchet")) {
 556                                 a->use_komi_ratchet = !optval || atoi(optval);
 557                         } else if (!strcasecmp(optname, "losing_komi_ratchet")) {
 558                                 a->losing_komi_ratchet = !optval || atoi(optval);
 559                         } else if (!strcasecmp(optname, "komi_ratchet_age") && optval) {
 560                                 a->komi_ratchet_maxage = atoi(optval);
 561
 562                                 /* score indicator settings */
 563                         } else if (!strcasecmp(optname, "adapter") && optval) {
 564                                 /* Adaptatation method. */
 565                                 if (!strcasecmp(optval, "sigmoid")) {
 566                                         a->adapter = adapter_sigmoid;
 567                                 } else if (!strcasecmp(optval, "linear")) {
 568                                         a->adapter = adapter_linear;
 569                                 } else {
 570                                         fprintf(stderr, "UCT: Invalid adapter %s\n", optval);
 571                                         exit(1);
 572                                 }
 573                         } else if (!strcasecmp(optname, "adapt_base") && optval) {
 574                                 /* Adaptation base rate; see above. */
 575                                 a->adapt_base = atof(optval);
 576                         } else if (!strcasecmp(optname, "adapt_rate") && optval) {
 577                                 /* Adaptation slope; see above. */
 578                                 a->adapt_rate = atof(optval);
 579                         } else if (!strcasecmp(optname, "adapt_phase") && optval) {
 580                                 /* Adaptation phase shift; see above. */
 581                                 a->adapt_phase = atof(optval);
 582                         } else if (!strcasecmp(optname, "adapt_moves") && optval) {
 583                                 /* Adaptation move amount; see above. */
 584                                 a->adapt_moves = atoi(optval);
 585                         } else if (!strcasecmp(optname, "adapt_aport")) {
 586                                 a->adapt_aport = !optval || atoi(optval);
 587                         } else if (!strcasecmp(optname, "adapt_dir") && optval) {
 588                                 /* Adaptation direction vector; see above. */
 589                                 a->adapt_dir = atof(optval);
 590
 591                         } else {
 592                                 fprintf(stderr, "uct: Invalid dynkomi argument %s or missing value\n", optname);
 593                                 exit(1);
 594                         }
 595                 }
 596         }
 597
 598         return d;
 599 }