gotch/nn/jit.go
2021-01-02 16:49:36 +11:00

99 lines
2.7 KiB
Go

package nn
import (
"io"
"log"
"strings"
ts "github.com/sugarme/gotch/tensor"
)
// TrainableCModule is a trainable version of JIT Pytorch module
//
// These modules can be created via TorchScript python API.
// See: https://pytorch.org/docs/stable/jit.html
type TrainableCModule struct {
Inner *ts.CModule
}
// TrainableCModuleLoad loads a PyTorch saved JIT module from a file and adds
// tensors (weights) to `varstore` so that module can be trained.
func TrainableCModuleLoad(p *Path, file string) (*TrainableCModule, error) {
inner, err := ts.ModuleLoadOnDevice(file, p.Device())
if err != nil {
return nil, err
}
namedTensors, err := inner.NamedParameters()
if err != nil {
return nil, err
}
// Add named tensors (weights) to varstore
for _, namedTensor := range namedTensors {
name := strings.ReplaceAll(namedTensor.Name, ".", "_")
requiresGrad := namedTensor.Tensor.MustRequiresGrad()
// NOTE: return is a newly created and added tensor in varstore.
// This tensor is different from input named tensor.
// If not using, just ignore it. Drop it, will drop tensor at varstore.
_ = p.Add(name, namedTensor.Tensor, requiresGrad)
// Clean-up named tensors.
namedTensor.Tensor.MustDrop()
}
return &TrainableCModule{inner}, nil
}
func TrainableCModuleLoadData(p *Path, stream io.Reader) (*TrainableCModule, error) {
inner, err := ts.ModuleLoadDataOnDevice(stream, p.Device())
if err != nil {
return nil, err
}
namedTensors, err := inner.NamedParameters()
if err != nil {
return nil, err
}
// Add named tensors (weights) to varstore
for _, namedTensor := range namedTensors {
name := strings.ReplaceAll(namedTensor.Name, ".", "_")
requiresGrad := namedTensor.Tensor.MustRequiresGrad()
// NOTE: return is a newly created and added tensor in varstore.
// This tensor is different from input named tensor.
// If not using, just ignore it. Drop it, will drop tensor at varstore.
_ = p.Add(name, namedTensor.Tensor, requiresGrad)
// Clean-up named tensors.
namedTensor.Tensor.MustDrop()
}
return &TrainableCModule{inner}, nil
}
// Save saves TrainableCModule to specified file.
func (m *TrainableCModule) Save(file string) error {
return m.Inner.Save(file)
}
// ForwardT implements ModuleT for TrainableCModule.
// NOTE: train parameter will not be used.
func (m *TrainableCModule) ForwardT(x *ts.Tensor, train bool) *ts.Tensor {
retVal, err := m.Inner.ForwardTs([]ts.Tensor{*x})
if err != nil {
log.Fatal(err)
}
return retVal
}
// SetTrain set TrainableCModule to train mode
func (m *TrainableCModule) SetTrain() {
m.Inner.SetTrain()
}
// SetEval set TrainableCModule to inference mode
func (m *TrainableCModule) SetEval() {
m.Inner.SetEval()
}