// the app
func TrainCF(dbName string, config *occult.Config, chunkSize int) *CF {
var db *store.Store
var err error
db, err = store.NewStore(dbName)
fatalIf(err)
defer db.Close()
var numGDIterations uint64 = 40
opt := &Options{
db: db,
chunkSize: chunkSize,
regularization: 0.1,
learnRate: 0.01,
numFactors: 4,
meanNorm: false,
alpha: 1,
}
app := occult.NewApp(config)
dataChunk := app.AddSource(movieFunc, opt, nil)
cfProc := app.Add(cfFunc, opt, dataChunk)
aggCFProc := app.Add(aggCFFunc, opt, cfProc)
mfProc := app.Add(mfFunc, opt, dataChunk, aggCFProc)
// If server, stays here forever, otherwise keep going.
app.Run()
glog.Infof("num logical CPUs: %d", runtime.NumCPU())
start := time.Now()
y, ey := mfProc(numGDIterations) // the index is the # iterations
if ey != nil {
glog.Fatal(ey)
}
end := time.Now()
d := end.Sub(start)
glog.Infof("train duration: %v", d)
app.Shutdown()
return y.(*CF)
}
func EvalCF(dbTest string, config *occult.Config, cf *CF) {
db, err := store.NewStore(dbTest)
fatalIf(err)
defer db.Close()
opt := &EvalOptions{
db: db,
cf: cf,
globalMean: cf.GlobalMean(),
sqErr: &SqErr{},
}
app := occult.NewApp(config)
evalProc := app.AddSource(evalFunc, opt, nil)
var i uint64
for {
v, e := evalProc(i)
if e != nil && e != occult.ErrEndOfArray {
glog.Fatal(e)
}
if v != nil {
glog.V(5).Infof("chunk[%4d]: %v", i, v)
}
if e == occult.ErrEndOfArray {
glog.V(3).Infof("end of array found at index %d", i)
break
}
i++
}
n := float64(opt.sqErr.n)
glog.Infof("N:%.0f, alpha:%.2f", n, cf.alpha)
glog.Infof("%20s: %.4f", "Global Mean", math.Sqrt(opt.sqErr.globalMean/n))
glog.Infof("%20s: %.4f", "Adj. User Mean", math.Sqrt(opt.sqErr.weightedUserMean/n))
glog.Infof("%20s: %.4f", "Item Mean", math.Sqrt(opt.sqErr.weightedItemMean/n))
glog.Infof("%20s: %.4f", "Simple MF", math.Sqrt(opt.sqErr.mf/n))
}