func vecFromString(s string, g *poem.Generator) []float64 {
v := make([]float64, g.InputSize())
c, ok := g.Dataset.Chars[s]
if !ok {
return v
}
v[c] = 1
return v
}
func sample(output []float64, gen *poem.Generator) ([]float64, int) {
var characterIndex int
r := rand.Float64()
var sum float64
for i, v := range output {
sum += v
if sum >= r {
characterIndex = i
break
}
}
input := make([]float64, gen.InputSize())
input[characterIndex] = 1
return input, characterIndex
}
func predict(c ntm.Controller, shi [][]string, gen *poem.Generator) [][]float64 {
machine := ntm.MakeEmptyNTM(c)
// Feed the poem constraints into the NTM.
numChar := 0
output := make([][]float64, 0)
for _, line := range shi {
for _, s := range line {
numChar += 1
input := vecFromString(s, gen)
machine, output = forward(machine, input, output)
}
numChar += 1
input := gen.Linefeed()
machine, output = forward(machine, input, output)
}
input := gen.EndOfPoem()
machine, output = forward(machine, input, output)
input = make([]float64, gen.InputSize())
machine, output = forward(machine, input, output)
// Follow the predictions of the NTM.
i := 1
for _, line := range shi {
for _, s := range line {
if s != "" {
input = vecFromString(s, gen)
} else {
input, _ = sample(output[len(output)-1], gen)
}
machine, output = forward(machine, input, output)
i++
}
if i >= numChar {
break
}
input, _ = sample(output[len(output)-1], gen)
machine, output = forward(machine, input, output)
i++
}
return output
}
func showPrediction(pred [][]float64, gen *poem.Generator, oripoem [][]string) {
ps := make([]string, len(pred))
// Prepare a slice representation of the poem constraints.
i := len(pred)/2 + 1
poema := make([]string, len(pred))
for _, line := range oripoem {
for _, c := range line {
if c != "" {
poema[i] = c
}
i++
}
poema[i] = poem.CharLinefeed
i++
}
// Determine the final characters from the predicted probability densities, with the following requirements:
// * The choosen character is the same as the input constraints.
// * The choosen characters are unique among themselves.
res := make([][]poem.Char, len(pred))
for i, p := range pred {
if i < len(pred)/2+1 {
ps[i] = ""
} else if poema[i] != "" {
ps[i] = poema[i]
} else {
sorted := gen.SortOutput(p)
for _, c := range sorted {
if c.S == poem.CharUnknown || c.S == poem.CharLinefeed {
continue
}
var dup bool = false
for _, psc := range ps {
if psc == c.S {
dup = true
break
}
}
if !dup {
ps[i] = c.S
break
}
}
}
res[i] = gen.SortOutput(p)[0:5]
}
// Print the probability densities.
for i, chars := range res {
log.Printf("%s -> %v", ps[i], chars)
if i == len(res)/2 {
log.Printf("-------------")
}
}
// Print the final generated poem.
s := "\n"
for _, c := range ps[len(ps)/2+1:] {
if c == poem.CharLinefeed {
s += "\n"
} else {
s += c
}
}
log.Printf(s)
}