Exemple #1
0
func (i *ITM) Threshold(cutoff float64) {
	for _, d := range rand.Perm(i.M) {
		for n := 0; n < i.N[d]; n++ {
			i.unsetZ(d, n)
			counts := i.conditional(d, n)
			util.Normalize(counts)

			bestZ := -1
			bestP := math.Inf(-1)
			useBest := true
			for z, count := range counts {
				if count > bestP {
					bestZ = z
					bestP = count
				}

				if count < cutoff {
					counts[z] = 0
				} else {
					useBest = false
				}
			}

			if useBest {
				i.setZ(d, n, bestZ)
			} else {
				i.setZ(d, n, util.SampleCounts(counts))
			}
		}
	}
}
Exemple #2
0
func (i *ITM) Gibbs() {
	for _, d := range rand.Perm(i.M) {
		for n := 0; n < i.N[d]; n++ {
			i.unsetZ(d, n)
			z := util.SampleCounts(i.conditional(d, n))
			i.setZ(d, n, z)
		}
	}
}
Exemple #3
0
func (l *LDA) Gibbs() {
	for _, d := range rand.Perm(l.M) {
		for n := 0; n < l.N[d]; n++ {
			l.unsetZ(d, n)
			z := util.SampleCounts(l.conditional(d, n))
			l.setZ(d, n, z)
		}
	}
}
Exemple #4
0
func (i *ITM) AnnealedGibbs(temp float64) {
	tempInv := 1 / temp
	for _, d := range rand.Perm(i.M) {
		for n := 0; n < i.N[d]; n++ {
			i.unsetZ(d, n)
			counts := i.conditional(d, n)
			for z := 0; z < i.T; z++ {
				counts[z] = math.Pow(counts[z], tempInv)
			}
			z := util.SampleCounts(counts)
			i.setZ(d, n, z)
		}
	}
}
Exemple #5
0
func (i *ITM) Coinflip(pMax float64) {
	for _, d := range rand.Perm(i.M) {
		for n := 0; n < i.N[d]; n++ {
			i.unsetZ(d, n)
			var z int
			if rand.Float64() < pMax {
				z = util.Argmax(i.conditional(d, n))
			} else {
				z = util.SampleCounts(i.conditional(d, n))
			}
			i.setZ(d, n, z)
		}
	}
}
Exemple #6
0
func (i *ITM) SampleTopN(n int) {
	for _, d := range rand.Perm(i.M) {
		for w := 0; w < i.N[d]; w++ {
			i.unsetZ(d, w)

			allCounts := i.conditional(d, w)
			topCounts := make([]float64, i.T)
			for _, z := range util.TopN(util.FloatCounts(allCounts), n) {
				topCounts[z] = allCounts[z]
			}

			z := util.SampleCounts(topCounts)
			i.setZ(d, w, z)
		}
	}
}