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#include "ccrp.h"
#include <vector>
#include <iostream>
#include "tdict.h"
#include "transliterations.h"
using namespace std;
MT19937 rng;
ostream& operator<<(ostream&os, const vector<int>& v) {
os << '[' << v[0];
if (v.size() == 2) os << ' ' << v[1];
return os << ']';
}
struct Base {
Base() : llh(), v(2), v1(1), v2(1), crp(0.25, 0.5) {}
inline double p0(const vector<int>& x) const {
double p = 0.75;
if (x.size() == 2) p = 0.25;
p *= 1.0 / 3.0;
if (x.size() == 2) p *= 1.0 / 3.0;
return p;
}
double est_deriv_prob(int a, int b, int seg) const {
assert(a > 0 && a < 4); // a \in {1,2,3}
assert(b > 0 && b < 4); // b \in {1,2,3}
assert(seg == 0 || seg == 1); // seg \in {0,1}
if (seg == 0) {
v[0] = a;
v[1] = b;
return crp.prob(v, p0(v));
} else {
v1[0] = a;
v2[0] = b;
return crp.prob(v1, p0(v1)) * crp.prob(v2, p0(v2));
}
}
double est_marginal_prob(int a, int b) const {
return est_deriv_prob(a,b,0) + est_deriv_prob(a,b,1);
}
int increment(int a, int b, double* pw = NULL) {
double p1 = est_deriv_prob(a, b, 0);
double p2 = est_deriv_prob(a, b, 1);
//p1 = 0.5; p2 = 0.5;
int seg = rng.SelectSample(p1,p2);
double tmp = 0;
if (!pw) pw = &tmp;
double& w = *pw;
if (seg == 0) {
v[0] = a;
v[1] = b;
w = crp.prob(v, p0(v)) / p1;
if (crp.increment(v, p0(v), &rng)) {
llh += log(p0(v));
}
} else {
v1[0] = a;
w = crp.prob(v1, p0(v1)) / p2;
if (crp.increment(v1, p0(v1), &rng)) {
llh += log(p0(v1));
}
v2[0] = b;
w *= crp.prob(v2, p0(v2));
if (crp.increment(v2, p0(v2), &rng)) {
llh += log(p0(v2));
}
}
return seg;
}
void increment(int a, int b, int seg) {
if (seg == 0) {
v[0] = a;
v[1] = b;
if (crp.increment(v, p0(v), &rng)) {
llh += log(p0(v));
}
} else {
v1[0] = a;
if (crp.increment(v1, p0(v1), &rng)) {
llh += log(p0(v1));
}
v2[0] = b;
if (crp.increment(v2, p0(v2), &rng)) {
llh += log(p0(v2));
}
}
}
void decrement(int a, int b, int seg) {
if (seg == 0) {
v[0] = a;
v[1] = b;
if (crp.decrement(v, &rng)) {
llh -= log(p0(v));
}
} else {
v1[0] = a;
if (crp.decrement(v1, &rng)) {
llh -= log(p0(v1));
}
v2[0] = b;
if (crp.decrement(v2, &rng)) {
llh -= log(p0(v2));
}
}
}
double log_likelihood() const {
return llh + crp.log_crp_prob();
}
double llh;
mutable vector<int> v, v1, v2;
CCRP<vector<int> > crp;
};
int main(int argc, char** argv) {
double tl = 0;
const int ITERS = 1000;
const int PARTICLES = 20;
const int DATAPOINTS = 50;
WordID x = TD::Convert("souvenons");
WordID y = TD::Convert("remember");
vector<WordID> src; TD::ConvertSentence("s o u v e n o n s", &src);
vector<WordID> trg; TD::ConvertSentence("r e m e m b e r", &trg);
// Transliterations xx;
// xx.Initialize(x, src, y, trg);
// return 1;
for (int j = 0; j < ITERS; ++j) {
Base b;
vector<int> segs(DATAPOINTS);
SampleSet<double> ss;
vector<int> sss;
for (int i = 0; i < DATAPOINTS; i++) {
ss.clear();
sss.clear();
int x = ((i / 10) % 3) + 1;
int y = (i % 3) + 1;
//double ep = b.est_marginal_prob(x,y);
//cerr << "est p(" << x << "," << y << ") = " << ep << endl;
for (int n = 0; n < PARTICLES; ++n) {
double w;
int seg = b.increment(x,y,&w);
//cerr << seg << " w=" << w << endl;
ss.add(w);
sss.push_back(seg);
b.decrement(x,y,seg);
}
int seg = sss[rng.SelectSample(ss)];
b.increment(x, y, seg);
//cerr << "Selected: " << seg << endl;
//return 1;
segs[i] = seg;
}
tl += b.log_likelihood();
}
cerr << "LLH=" << tl / ITERS << endl;
}
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