7 DEBUG_DEFINE_DEBUGF(value);
9 typedef struct { int mass, volu; } CommodInfo;
10 static int commodstablesz;
11 static CommodInfo *commodstable;
13 static sqlite3_stmt *ss_ipair_dist, *ss_ipair_trades;
14 static sqlite3_stmt *ss_ite_buy, *ss_ite_sell;
16 #define MAX_LEGS (MAX_ROUTELEN-1)
19 int commodid, src_price, dst_price;
22 #define TRADES_PER_BLOCK 10
24 typedef struct TradesBlock{
25 struct TradesBlock *next;
26 Trade t[TRADES_PER_BLOCK];
30 double distance_loss_factor;
35 IslandPair ***ipairs; /* ipairs[sislandid][dislandid] */
37 typedef struct IslandTradeEnd {
38 struct IslandTradeEnd *next;
41 unsigned long generation;
46 IslandTradeEnd *src, *dst;
47 } IslandTradeEndHeads;
49 IslandTradeEndHeads *itradeends;
50 /* itradeends[islandid].{src,dst}->commodid etc. */
53 static unsigned long generation;
55 static int nconstraint_rows;
56 static int constraint_rows[1+2+3*MAX_LEGS];
57 static double constraint_coeffs[1+2+3*MAX_LEGS];
58 /* dummy0, src, dst, for_each_leg( [mass], [volume], [capital] ) */
60 static void add_constraint(int row, double coefficient) {
61 nconstraint_rows++; /* glpk indices start from 1 !!! */
62 constraint_rows [nconstraint_rows]= row;
63 constraint_coeffs[nconstraint_rows]= coefficient;
66 static void avail_c(const Trade *t, IslandTradeEnd **trades,
67 int price, const char *srcdst,
68 int islandid, sqlite3_stmt *ss_ite) {
69 /* find row number of trade availability constraint */
70 IslandTradeEnd *search;
72 for (search= *trades; search; search=search->next)
73 if (search->commodid==t->commodid && search->price==price)
75 /* not found, add new row */
77 search= mmalloc(sizeof(*search));
78 search->commodid= t->commodid;
80 search->next= *trades;
81 search->generation= 0;
83 SQL_BIND(ss_ite, 1, islandid);
84 SQL_BIND(ss_ite, 2, t->commodid);
85 SQL_BIND(ss_ite, 3, price);
86 assert(SQL_STEP(ss_ite));
87 search->qty= sqlite3_column_int(ss_ite, 0);
88 SQL_MUST( sqlite3_reset(ss_ite) );
93 if (search->generation != generation) {
94 search->rownum= lpx_add_rows(lp, 1);
95 lpx_set_row_bnds(lp, search->rownum, LPX_UP, 0, search->qty);
98 char *name= masprintf("%s_c%d_%d",srcdst,t->commodid,price);
99 lpx_set_row_name(lp,search->rownum,name);
102 search->generation= generation;
105 add_constraint(search->rownum, 1.0);
108 static int setup_leg_constraints(double max_thing, int legs, const char *wh) {
110 if (max_thing < 0 || !legs) return -1;
111 startrow= lpx_add_rows(lp, legs);
112 for (leg=0; leg<legs; leg++) {
113 int row= leg+startrow;
114 lpx_set_row_bnds(lp, row, LPX_UP, 0, max_thing);
116 char *name= masprintf("max_leg%d_%s",leg,wh);
117 lpx_set_row_name(lp,row,name);
124 static void add_leg_c(int startrow, int leg, double value) {
125 if (startrow<=0) return;
127 add_constraint(startrow+leg, value);
130 static IslandPair *ipair_get(int si, int di) {
131 IslandPair *ip, **ipa;
133 assert(si < islandtablesz);
134 assert(di < islandtablesz);
136 if (!(ipa= ipairs[si])) {
137 ipa= ipairs[si]= mcalloc(sizeof(*ipa) * islandtablesz);
142 ipa[di]= ip= mmalloc(sizeof(*ip));
145 int inblock= TRADES_PER_BLOCK;
146 TradesBlock *block= 0;
148 debugf("VALUE ipair_get(%d,%d) running...\n", si,di);
149 SQL_MUST( sqlite3_bind_int(ss_ipair_dist, 1, si) );
150 SQL_MUST( sqlite3_bind_int(ss_ipair_dist, 2, di) );
151 assert(SQL_STEP(ss_ipair_dist));
152 int dist= sqlite3_column_int(ss_ipair_dist, 0);
153 ip->distance_loss_factor= pow(distance_loss_factor_per_league, dist);
154 sqlite3_reset(ss_ipair_dist);
156 SQL_MUST( sqlite3_bind_int(ss_ipair_trades, 1, si) );
157 SQL_MUST( sqlite3_bind_int(ss_ipair_trades, 2, di) );
159 while (SQL_STEP(ss_ipair_trades)) {
160 if (inblock == TRADES_PER_BLOCK) {
161 block= mmalloc(sizeof(*block));
162 block->next= ip->trades;
167 for (i=0, irp=&block->t[inblock].commodid; i<3; i++, irp++)
168 *irp= sqlite3_column_int(ss_ipair_trades, i);
172 if (inblock < TRADES_PER_BLOCK)
173 block->t[inblock].commodid= -1;
175 sqlite3_reset(ss_ipair_trades);
180 double value_route(int nislands, const int *islands) {
183 /* We need to construct the LP problem. GLPK talks
184 * about rows and columns, which are numbered from 1.
186 * Each column is a `structural variable' ie one of the entries in
187 * the objective function. In our case the set of structural
188 * variable is, for each port, the set of Trades which collect at
189 * that island. (We use `port' to mean `specific visit to an
190 * island' so if an island appears more than once so do its trades.)
191 * We don't need to worry about crossing with all the possible
192 * delivery locations as we always deliver on the first port.
193 * We will call such a structural variable a Flow, for brevity.
195 * We iterate over the possible Flows adding them as columns as we
196 * go, and also adding their entries to the various constraints.
198 * Each row is an `auxiliary variable' ie one of the constraints.
199 * We have two kinds of constraint:
200 * - mass/volume/capital: one constraint for each sailed leg
201 * (unless relevant constraint is not satisfied)
202 * - quantity of commodity available for collection
203 * or delivery at particular price and island
204 * The former are numbered predictably: we have first all the mass
205 * limits, then all the volume limits, then all the capital limits
206 * (as applicable) - one for each leg, ie one for each entry
207 * in islands except the first.
209 * The latter are added as needed and the row numbers are stored in
210 * a data structure for later reuse.
213 assert(nislands >= 1);
214 assert(++generation);
217 lp= lpx_create_prob();
218 lpx_set_obj_dir(lp, LPX_MAX);
219 lpx_set_int_parm(lp, LPX_K_MSGLEV, DEBUGP(lp) ? 3 : 1);
222 lpx_set_prob_name(lp,(char*)"value_route");
223 lpx_set_obj_name(lp,(char*)"profit");
226 int legs= nislands-1;
227 int mass_constraints= setup_leg_constraints(max_mass, legs, "mass");
228 int volu_constraints= setup_leg_constraints(max_volu, legs, "volu");
229 int capi_constraints= setup_leg_constraints(max_capi, legs, "capi");
231 double delay_slot_loss_factor= 1.0;
234 s++, delay_slot_loss_factor *= LOSS_FACTOR_PER_DELAY_SLOT) {
237 for (d=s; d<nislands; d++) {
240 for (already_d=s+1; already_d<d; already_d++)
241 if (islands[already_d] == di)
242 /* visited this island already since we left s, uninteresting */
246 /* route has returned to si, no need to think more about s */
249 /*----- actually add these trades to the LP problem -----*/
251 IslandPair *ip= ipair_get(islands[s], islands[d]);
252 TradesBlock *block= ip->trades;
253 int tradestodo= ip->ntrades;
258 int col= lpx_add_cols(lp,ip->ntrades);
260 double loss_factor= delay_slot_loss_factor * ip->distance_loss_factor;
262 while (tradestodo-- >0) {
263 if (inblock >= TRADES_PER_BLOCK) {
267 Trade *t= &block->t[inblock++];
269 debugf(" TRADE %d#%d..%d#%d %d %d-%d\n",
270 si,s, di,d, t->commodid, t->src_price, t->dst_price);
274 avail_c(t, &itradeends[s].src, t->src_price, "src", si, ss_ite_sell);
275 avail_c(t, &itradeends[d].dst, t->dst_price, "dst", di, ss_ite_buy);
278 for (leg=s; leg<d; leg++) {
279 add_leg_c(mass_constraints, leg, commodstable[t->commodid].mass);
280 add_leg_c(volu_constraints, leg, commodstable[t->commodid].volu);
281 add_leg_c(capi_constraints, leg, t->src_price);
284 double unit_profit= (t->dst_price - t->src_price) * loss_factor;
285 debugf(" unit profit %f\n", unit_profit);
287 lpx_set_col_bnds(lp, col, LPX_LO, 0, 0);
288 lpx_set_obj_coef(lp, col, unit_profit);
289 lpx_set_mat_col(lp, col, nconstraint_rows,
290 constraint_rows, constraint_coeffs);
293 char *name= masprintf("c%d_p%d_%d_p%d_%d",
294 t->commodid, s, t->src_price, d, t->dst_price);
295 lpx_set_col_name(lp, col, name);
300 } /* while (tradestodo-- >0) */
302 /*----- that's done adding these trades to the LP problem -----*/
311 if (lpx_get_num_cols(lp)) {
313 lpx_write_cpxlp(lp, (char*)DEBUG_DEV);
315 int ipr= lpx_interior(lp);
316 assert(ipr==LPX_E_OK);
319 lpx_print_ips(lp, (char*)DEBUG_DEV);
321 assert(lpx_ipt_status(lp) == LPX_T_OPT);
322 profit= lpx_ipt_obj_val(lp);
331 void setup_value(void) {
335 commodstablesz= sql_single_int("SELECT max(commodid) FROM commods") + 1;
336 commodstable= mmalloc(sizeof(*commodstable)*commodstablesz);
337 for (i=0; i<commodstablesz; i++)
338 commodstable[i].mass= commodstable[i].volu= -1;
340 itradeends= mcalloc(sizeof(*itradeends) * islandtablesz);
343 "SELECT commodid,unitmass,unitvolume FROM commods");
344 while (SQL_STEP(sst)) {
345 int id= sqlite3_column_int(sst,0);
346 assert(id>=0 && id<commodstablesz);
347 commodstable[id].mass= sqlite3_column_int(sst,1);
348 commodstable[id].volu= sqlite3_column_int(sst,2);
350 sqlite3_finalize(sst);
352 SQL_PREPARE(ss_ipair_dist,
353 " SELECT dist FROM dists\n"
354 " WHERE aiid=? and biid=?");
356 SQL_PREPARE(ss_ipair_trades,
358 " sell.commodid commodid,\n"
359 " sell.price src_price,\n"
360 " buy.price dst_price\n"
361 " FROM sell JOIN buy\n"
362 " ON sell.commodid = buy.commodid\n"
363 " AND buy.price > sell.price\n"
364 " WHERE sell.islandid=?\n"
365 " AND buy.islandid=?");
368 SQL_PREPARE(ss_ite_##bs, \
372 " WHERE islandid=?\n" \
373 " AND commodid=?\n" \
379 ipairs= mcalloc(sizeof(*ipairs) * islandtablesz);