plunkerでtensorflow.js その19

#概要

plunkerでtensorflow.jsやってみた。
callbacks使ってみた。

#サンプルコード

tf.setBackend('cpu');
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
function draw(data, n) {
	var hc = n * 100 + 100;
	ctx.strokeStyle = "#f00";
	ctx.lineWidth = 1;
	ctx.moveTo(0, hc);
	for (var i = 1; i < data.length; i++)
	{
		ctx.lineTo(i, hc - data[i] * 30);
	}
	ctx.stroke();
}

const model = tf.sequential();
model.add(tf.layers.dense({
	units: 40,
	activation: 'tanh',
	inputShape: [1]
}));
model.add(tf.layers.dense({
	units: 1,
	activation: 'tanh'
}));
model.compile({
	optimizer: 'adam',
	loss: 'meanSquaredError'
});
const buffer = tf.buffer([200, 1]);
const buffer2 = tf.buffer([200, 1]);
b = [];
for (var i = 0; i < 200; i++)
{
	var x = i / 30.0;
	var y = Math.sin(x);
	b.push(y);
	buffer.set(x, i, 0);
	buffer2.set(y, i, 0);
}
draw(b, 0);
const xs = buffer.toTensor();
const ys = buffer2.toTensor();
c = [];
model.fit(xs, ys, {
	batchSize: 200,
	epochs: 2000,
 	callbacks: {
		onEpochEnd: (epoch, logs) => {
			if (epoch % 10 == 0) 
			{
			  c.push(logs.loss);
			  draw(c, 1);
			}
		},
	}
}).then((d) => {
	var str = "loss = ";
	str += d.history.loss[0];
	alert(str);
	p = [];
	for (i = 0; i < 200; i++)
	{
		var x =  i / 30.0;
		var pre = model.predict(tf.tensor2d([[x]], [1, 1]));
		var f = pre.dataSync();
		p.push(f);
	}
	draw(p, 2);
});

#成果物

以上。