Add a size argument to the input layer (#916)

Author: ishii-norimi

lib/model/nns/layer/index.js

@@ -181,7 +181,7 @@ import Tensor from '../../../util/tensor.js'
  * { type: 'huber' } |
  * { type: 'identity' } |
  * { type: 'include', net: NeuralNetwork | object[], input_to?: string, train?: boolean } |
- * { type: 'input', name?: string } |
+ * { type: 'input', name?: string, size?: number[] } |
  * { type: 'is_inf' } |
  * { type: 'is_nan' } |
  * { type: 'isigmoid', a?: number, alpha?: number } |

lib/model/nns/layer/input.js

@@ -1,4 +1,4 @@
-import Layer from './base.js'
+import Layer, { NeuralnetworkLayerException } from './base.js'
 import Matrix from '../../../util/matrix.js'
 import Tensor from '../../../util/tensor.js'
 
@@ -9,10 +9,12 @@ export default class InputLayer extends Layer {
 	/**
 	 * @param {object} config object
 	 * @param {string} [config.name] Name of the layer
+	 * @param {number[]} [config.size] Size of the layer
 	 */
-	constructor({ name = null, ...rest }) {
+	constructor({ name = null, size = null, ...rest }) {
 		super(rest)
 		this._name = name
+		this._size = size
 	}
 
 	bind({ input }) {
@@ -35,6 +37,13 @@ export default class InputLayer extends Layer {
 		} else {
 			this._o = new Matrix(1, 1, input)
 		}
+
+		if (this._size) {
+			const inSize = this._o.sizes
+			if (inSize.length !== this._size.length || this._size.some((v, i) => v != null && v !== inSize[i])) {
+				throw new NeuralnetworkLayerException(`Invalid input size`, [this])
+			}
+		}
 	}
 
 	calc() {

tests/lib/model/nns/layer/input.test.js

@@ -10,6 +10,35 @@ describe('layer', () => {
 		expect(layer).toBeDefined()
 	})
 
+	describe('bind', () => {
+		test.each([
+			[null, null],
+			[2, null],
+			[null, 3],
+			[2, 3],
+		])('valid dim length [%p, %p]', (...size) => {
+			expect.assertions(0)
+			const layer = new InputLayer({ size })
+
+			const x = Matrix.randn(2, 3).toArray()
+			layer.bind({ input: x })
+		})
+
+		test('invalid dim length', () => {
+			const layer = new InputLayer({ size: [null, null, null] })
+
+			const x = Matrix.randn(2, 3).toArray()
+			expect(() => layer.bind({ input: x })).toThrow('Invalid input size')
+		})
+
+		test('invalid dim value', () => {
+			const layer = new InputLayer({ size: [3, 2] })
+
+			const x = Matrix.randn(2, 3).toArray()
+			expect(() => layer.bind({ input: x })).toThrow('Invalid input size')
+		})
+	})
+
 	describe('calc', () => {
 		test('scalar', () => {
 			const layer = new InputLayer({})