Gluon hello world

Gluon is a standard implemented by MXNet and which would unify the API of diverse frameworks. It has been superseded by ONNX.

Gist

    from mxnet import gluon

    import mxnet as mx
    import numpy as np
    x_input = mx.nd.empty((1, 5), mx.cpu())
    x_input[:] = np.array([[1,2,3,4,5]], np.float32)

    y_input = mx.nd.empty((1, 5), mx.cpu())
    y_input[:] = np.array([[10, 15, 20, 22.5, 25]], np.float32)


    net = gluon.nn.Sequential()
    with net.name_scope():
        net.add(gluon.nn.Dense(16, activation="relu"))
        net.add(gluon.nn.Dense(len(y_input)))


    net.collect_params().initialize(mx.init.Normal(), ctx=mx.cpu())


    softmax_cross_entropy = gluon.loss.SoftmaxCrossEntropyLoss()
    trainer = gluon.Trainer(net.collect_params(), 'adam', {'learning_rate': .1})


    n_epochs = 10

    for e in range(n_epochs):
        for i in range(len(x_input)):
            input = x_input[i]
            target = y_input[i]
            with mx.autograd.record():
                output = net(input)
                loss = softmax_cross_entropy(output, target)
                loss.backward()
            trainer.step(input.shape[0])