com.expleague.ml.models.nn.nfa.WeightsCalculator Maven / Gradle / Ivy
package com.expleague.ml.models.nn.nfa;
import com.expleague.commons.func.Computable;
import com.expleague.commons.math.vectors.Mx;
import com.expleague.commons.math.vectors.Vec;
import com.expleague.commons.math.vectors.impl.ThreadLocalArrayVec;
import com.expleague.commons.math.vectors.impl.mx.VecBasedMx;
/**
* User: solar
* Date: 29.06.15
* Time: 17:12
*/
class WeightsCalculator implements Computable {
private final int statesCount;
private final int wStart;
private final int wLen;
private boolean[] dropOut;
WeightsCalculator(int statesCount, int wStart, int wLen) {
this.statesCount = statesCount;
this.wStart = wStart;
this.wLen = wLen;
}
final ThreadLocalArrayVec w = new ThreadLocalArrayVec();
public Mx computeInner(Vec betta) {
final VecBasedMx b = new VecBasedMx(statesCount - 1, betta.sub(wStart, wLen));
final VecBasedMx w = new VecBasedMx(statesCount, this.w.get(statesCount * statesCount));
for (int i = 0; i < statesCount - 1; i++) {
if (dropOut[i])
continue;
double sum = 1;
for (int j = 0; j < statesCount - 1; j++) {
if (dropOut[j])
continue;
sum += Math.exp(b.get(i, j));
}
for (int j = 0; j < statesCount; j++) {
if (dropOut[j])
continue;
final double selectedExp = j < statesCount - 1 ? Math.exp(b.get(i, j)) : 1;
w.set(j, i, selectedExp / sum);
}
}
return w;
}
private Vec cacheArg;
private Mx cacheVal;
@Override
public Mx compute(Vec betta) {
if (!betta.isImmutable())
return computeInner(betta);
if (betta == cacheArg)
return cacheVal;
cacheArg = betta;
return cacheVal = computeInner(betta);
}
public void setDropOut(boolean[] dropOut) {
cacheArg = null;
this.dropOut = dropOut;
}
}