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-rw-r--r--gi/clda/src/crp.h162
1 files changed, 0 insertions, 162 deletions
diff --git a/gi/clda/src/crp.h b/gi/clda/src/crp.h
index 13596cbf..865c41ac 100644
--- a/gi/clda/src/crp.h
+++ b/gi/clda/src/crp.h
@@ -2,20 +2,12 @@
#define _CRP_H_
// shamelessly adapted from code by Phil Blunsom and Trevor Cohn
-// There are TWO CRP classes here: CRPWithTableTracking tracks the
-// (expected) number of customers per table, and CRP just tracks
-// the number of customers / dish.
-// If you are implementing a HDP model, you should use CRP for the
-// base distribution and CRPWithTableTracking for the dependent
-// distribution.
-#include <iostream>
#include <map>
#include <boost/functional/hash.hpp>
#include <tr1/unordered_map>
#include "prob.h"
-#include "sampler.h" // RNG
template <typename DishType, typename Hash = boost::hash<DishType> >
class CRP {
@@ -59,158 +51,4 @@ void CRP<Dish,Hash>::decrement(const Dish& dish) {
--total_customers_;
}
-template <typename DishType, typename Hash = boost::hash<DishType>, typename RNG = MT19937>
-class CRPWithTableTracking {
- public:
- CRPWithTableTracking(double alpha, RNG* rng) :
- alpha_(alpha), palpha_(alpha), total_customers_(),
- total_tables_(), rng_(rng) {}
-
- // seat a customer for dish d, returns the delta in tables
- // with customers
- int increment(const DishType& d, const prob_t& p0 = prob_t::One());
- int decrement(const DishType& d);
- void erase(const DishType& dish);
-
- inline int count(const DishType& dish) const {
- const typename MapType::const_iterator i = counts_.find(dish);
- if (i == counts_.end()) return 0; else return i->second.count_;
- }
- inline prob_t prob(const DishType& dish) const {
- return (prob_t(count(dish) + alpha_)) / prob_t(total_customers_ + alpha_);
- }
- inline prob_t prob(const DishType& dish, const prob_t& p0) const {
- return (prob_t(count(dish)) + palpha_ * p0) / prob_t(total_customers_ + alpha_);
- }
- private:
- struct TableInfo {
- TableInfo() : count_(), tables_() {}
- int count_; // total customers eating dish
- int tables_; // total tables labeled with dish
- std::map<int, int> table_histogram_; // num customers at table -> number tables
- };
- typedef std::tr1::unordered_map<DishType, TableInfo, Hash> MapType;
-
- inline prob_t prob_share_table(const double& customer_count) const {
- if (customer_count)
- return prob_t(customer_count) / prob_t(customer_count + alpha_);
- else
- return prob_t::Zero();
- }
- inline prob_t prob_new_table(const double& customer_count, const prob_t& p0) const {
- if (customer_count)
- return palpha_ * p0 / prob_t(customer_count + alpha_);
- else
- return p0;
- }
-
- MapType counts_;
- const double alpha_;
- const prob_t palpha_;
- int total_customers_;
- int total_tables_;
- RNG* rng_;
-};
-
-template <typename Dish, typename Hash, typename RNG>
-int CRPWithTableTracking<Dish,Hash,RNG>::increment(const Dish& dish, const prob_t& p0) {
- TableInfo& tc = counts_[dish];
-
- //std::cerr << "\nincrement for " << dish << " with p0 " << p0 << "\n";
- //std::cerr << "\tBEFORE histogram: " << tc.table_histogram_ << " ";
- //std::cerr << "count: " << tc.count_ << " ";
- //std::cerr << "tables: " << tc.tables_ << "\n";
-
- // seated at a new or existing table?
- prob_t pshare = prob_share_table(tc.count_);
- prob_t pnew = prob_new_table(tc.count_, p0);
-
- //std::cerr << "\t\tP0 " << p0 << " count(dish) " << count(dish)
- // << " tables " << tc
- // << " p(share) " << pshare << " p(new) " << pnew << "\n";
-
- int delta = 0;
- if (tc.count_ == 0 || rng_->SelectSample(pshare, pnew) == 1) {
- // assign to a new table
- ++tc.tables_;
- ++tc.table_histogram_[1];
- ++total_tables_;
- delta = 1;
- } else {
- // can't share a table if there are no other customers
- assert(tc.count_ > 0);
-
- // randomly assign to an existing table
- // remove constant denominator from inner loop
- int r = static_cast<int>(rng_->next() * tc.count_);
- for (std::map<int,int>::iterator hit = tc.table_histogram_.begin();
- hit != tc.table_histogram_.end(); ++hit) {
- r -= hit->first * hit->second;
- if (r <= 0) {
- ++tc.table_histogram_[hit->first+1];
- --hit->second;
- if (hit->second == 0)
- tc.table_histogram_.erase(hit);
- break;
- }
- }
- if (r > 0) {
- std::cerr << "CONSISTENCY ERROR: " << tc.count_ << std::endl;
- std::cerr << pshare << std::endl;
- std::cerr << pnew << std::endl;
- std::cerr << r << std::endl;
- abort();
- }
- }
- ++tc.count_;
- ++total_customers_;
- return delta;
-}
-
-template <typename Dish, typename Hash, typename RNG>
-int CRPWithTableTracking<Dish,Hash,RNG>::decrement(const Dish& dish) {
- typename MapType::iterator i = counts_.find(dish);
- if(i == counts_.end()) {
- std::cerr << "MISSING DISH: " << dish << std::endl;
- abort();
- }
-
- int delta = 0;
- TableInfo &tc = i->second;
-
- //std::cout << "\ndecrement for " << dish << " with p0 " << p0 << "\n";
- //std::cout << "\tBEFORE histogram: " << tc.table_histogram << " ";
- //std::cout << "count: " << count(dish) << " ";
- //std::cout << "tables: " << tc.tables << "\n";
-
- int r = static_cast<int>(rng_->next() * tc.count_);
- //std::cerr << "FOO: " << r << std::endl;
- for (std::map<int,int>::iterator hit = tc.table_histogram_.begin();
- hit != tc.table_histogram_.end(); ++hit) {
- r -= (hit->first * hit->second);
- if (r <= 0) {
- if (hit->first > 1)
- tc.table_histogram_[hit->first-1] += 1;
- else {
- --delta;
- --tc.tables_;
- --total_tables_;
- }
-
- --hit->second;
- if (hit->second == 0) tc.table_histogram_.erase(hit);
- break;
- }
- }
-
- assert(r <= 0);
-
- // remove the customer
- --tc.count_;
- --total_customers_;
- assert(tc.count_ >= 0);
- if (tc.count_ == 0) counts_.erase(i);
- return delta;
-}
-
#endif
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