nlpodyssey/spago

// Copyright 2019 spaGO Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package linear

import (
    "encoding/gob"

    "github.com/nlpodyssey/spago/ag"
    "github.com/nlpodyssey/spago/mat"
    "github.com/nlpodyssey/spago/mat/float"
    "github.com/nlpodyssey/spago/nn"
)

var _ nn.Model = &Model{}

// Model contains the serializable parameters.
type Model struct {
    nn.Module
    W *nn.Param
    B *nn.Param
}

func init() {
    gob.Register(&Model{})
}

// New returns a new model with parameters initialized to zeros.
func New[T float.DType](in, out int) *Model {
    return &Model{
        W: nn.NewParam(mat.NewDense[T](mat.WithShape(out, in))),
        B: nn.NewParam(mat.NewDense[T](mat.WithShape(out))),
    }
}

// WithBiasGrad allows you to enable or disable gradient propagation on bias (enabled by default).
func (m *Model) WithBiasGrad(value bool) *Model {
    m.B.SetRequiresGrad(value)
    return m
}

// Forward performs the forward step for each input node and returns the result.
func (m *Model) Forward(xs ...mat.Tensor) []mat.Tensor {
    ys := make([]mat.Tensor, len(xs))
    for i, x := range xs {
        ys[i] = ag.Affine(m.B, m.W, x)
    }
    return ys
}