gobrain
Neural Networks written in go
Getting Started
The version 1.0.0
includes just basic Neural Network functions such as Feed Forward and Elman Recurrent Neural Network.
A simple Feed Forward Neural Network can be constructed and trained as follows:
package main
import (
"github.com/goml/gobrain"
"math/rand"
)
func main() {
// set the random seed to 0
rand.Seed(0)
// create the XOR representation patter to train the network
patterns := [][][]float64{
{{0, 0}, {0}},
{{0, 1}, {1}},
{{1, 0}, {1}},
{{1, 1}, {0}},
}
// instantiate the Feed Forward
ff := &gobrain.FeedForward{}
// initialize the Neural Network;
// the networks structure will contain:
// 2 inputs, 2 hidden nodes and 1 output.
ff.Init(2, 2, 1)
// train the network using the XOR patterns
// the training will run for 1000 epochs
// the learning rate is set to 0.6 and the momentum factor to 0.4
// use true in the last parameter to receive reports about the learning error
ff.Train(patterns, 1000, 0.6, 0.4, true)
}
After running this code the network will be trained and ready to be used.
The network can be tested running using the Test
method, for instance:
ff.Test(patterns)
The test operation will print in the console something like:
[0 0] -> [0.057503945708445] : [0]
[0 1] -> [0.930100635071210] : [1]
[1 0] -> [0.927809966227284] : [1]
[1 1] -> [0.097408795324620] : [0]
Where the first values are the inputs, the values after the arrow ->
are the output values from the network and the values after :
are the expected outputs.
The method Update
can be used to predict the output given an input, for example:
inputs := []float64{1, 1}
ff.Update(inputs)
the output will be a vector with values ranging from 0
to 1
.
Recurrent Neural Network
This library implements Elman's Simple Recurrent Network.
To take advantage of this, one can use the SetContexts
function.
ff.SetContexts(1, nil)
In the example above, a single context will be created initilized with 0.5
. It is also possible
to create custom initilized contexts, for instance:
contexts := [][]float64{
{0.5, 0.8, 0.1}
}
Note that custom contexts must have the same size of hidden nodes + 1 (bias node), in the example above the size of hidden nodes is 2, thus the context has 3 values.
Changelog
- 1.0.0 - Added Feed Forward Neural Network with contexts from Elman RNN