From 8d89c02113402652d9c91a80cd2540521ab47038 Mon Sep 17 00:00:00 2001
From: Petr Baudis <pasky@ucw.cz>
Date: Sat, 7 Jan 2012 21:27:57 +0100
Subject: [PATCH] Pattern Probability Table: Introduce basic infrastructure

---
 Makefile      |  2 +-
 patternprob.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 patternprob.h | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 127 insertions(+), 1 deletion(-)
 create mode 100644 patternprob.c
 create mode 100644 patternprob.h

diff --git a/Makefile b/Makefile
index bfedb57..a19dc71 100644
--- a/Makefile
+++ b/Makefile
@@ -91,7 +91,7 @@ unexport INCLUDES
 INCLUDES=-I.
 
 
-OBJS=board.o gtp.o move.o ownermap.o pattern3.o pattern.o patternsp.o playout.o probdist.o random.o stone.o timeinfo.o network.o fbook.o
+OBJS=board.o gtp.o move.o ownermap.o pattern3.o pattern.o patternsp.o patternprob.o playout.o probdist.o random.o stone.o timeinfo.o network.o fbook.o
 SUBDIRS=random replay patternscan joseki montecarlo uct uct/policy playout tactics t-unit distributed
 
 all: all-recursive pachi
diff --git a/patternprob.c b/patternprob.c
new file mode 100644
index 0000000..6173417
--- /dev/null
+++ b/patternprob.c
@@ -0,0 +1,59 @@
+#define DEBUG
+#include <assert.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "board.h"
+#include "debug.h"
+#include "pattern.h"
+#include "patternsp.h"
+#include "patternprob.h"
+
+
+struct pattern_pdict *
+pattern_pdict_init(char *filename, struct pattern_config *pc)
+{
+	if (!filename)
+		filename = "patterns.prob";
+	FILE *f = fopen(filename, "r");
+	if (!f) {
+		if (DEBUGL(1))
+			fprintf(stderr, "No pattern probtable, will not use learned patterns.\n");
+		return NULL;
+	}
+
+	struct pattern_pdict *dict = calloc2(1, sizeof(*dict));
+	dict->pc = pc;
+	dict->table = calloc2(pc->spat_dict->nspatials + 1, sizeof(*dict->table));
+
+	char sbuf[1024];
+	while (fgets(sbuf, sizeof(sbuf), f)) {
+		struct pattern_prob *pb = calloc2(1, sizeof(*pb));
+		int c, o;
+
+		char *buf = sbuf;
+		if (buf[0] == '#') continue;
+		while (isspace(*buf)) buf++;
+		while (!isspace(*buf)) buf++; // we recompute the probability
+		while (isspace(*buf)) buf++;
+		c = strtol(buf, &buf, 10);
+		while (isspace(*buf)) buf++;
+		o = strtol(buf, &buf, 10);
+		pb->prob = (floating_t) c / o;
+		while (isspace(*buf)) buf++;
+		str2pattern(buf, &pb->p);
+
+		uint32_t spi = pattern2spatial(dict, &pb->p);
+		if (!dict->table[spi]) {
+			dict->table[spi] = pb;
+		} else {
+			struct pattern_prob *ppb = dict->table[spi];
+			while (ppb->next) ppb = ppb->next;
+			ppb->next = pb;
+		}
+	}
+
+	fclose(f);
+	return dict;
+}
diff --git a/patternprob.h b/patternprob.h
new file mode 100644
index 0000000..198a147
--- /dev/null
+++ b/patternprob.h
@@ -0,0 +1,67 @@
+#ifndef PACHI_PATTERNPROB_H
+#define PACHI_PATTERNPROB_H
+
+/* Pattern probability table. */
+
+#include <math.h>
+
+#include "board.h"
+#include "move.h"
+#include "pattern.h"
+
+
+/* The pattern probability table considers each pattern as a whole
+ * (not dividing it to individual features) and stores probability
+ * of the pattern being played. */
+
+/* The table primary key is the pattern spatial (most distinctive
+ * feature); within a single primary key chain, the entries are
+ * unsorted (for now). */
+
+struct pattern_prob {
+	struct pattern p;
+	floating_t prob;
+	struct pattern_prob *next;
+};
+
+struct pattern_pdict {
+	struct pattern_config *pc;
+
+	struct pattern_prob **table; /* [pc->spat_dict->nspatials + 1] */
+};
+
+/* Initialize the pdict data structure from a given file (pass NULL
+ * to use default filename). Returns NULL if the file with patterns
+ * has been found. */
+struct pattern_pdict *pattern_pdict_init(char *filename, struct pattern_config *pc);
+
+/* Return probability associated with given pattern. Returns NaN if
+ * the pattern cannot be found. */
+static floating_t pattern_prob(struct pattern_pdict *dict, struct pattern *p);
+
+/* Utility function - extract spatial id from a pattern. If the pattern
+ * has no spatial feature, it is represented by the highest spatial id
+ * plus one. */
+static uint32_t pattern2spatial(struct pattern_pdict *dict, struct pattern *p);
+
+
+static inline floating_t
+pattern_prob(struct pattern_pdict *dict, struct pattern *p)
+{
+	uint32_t spi = pattern2spatial(dict, p);
+	for (struct pattern_prob *pb = dict->table[spi]; pb; pb = pb->next)
+		if (pattern_eq(p, &pb->p))
+			return pb->prob;
+	return NAN; // XXX: We assume quiet NAN existence
+}
+
+static inline uint32_t
+pattern2spatial(struct pattern_pdict *dict, struct pattern *p)
+{
+	for (int i = 0; i < p->n; i++)
+		if (p->f[i].id == FEAT_SPATIAL)
+			return p->f[i].payload;
+	return dict->pc->spat_dict->nspatials;
+}
+
+#endif
-- 
2.11.4.GIT