@tensorflow/tfjs-layers
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TensorFlow layers API in JavaScript
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TypeScript
/**
* @license
* Copyright 2018 Google LLC
*
* Use of this source code is governed by an MIT-style
* license that can be found in the LICENSE file or at
* https://opensource.org/licenses/MIT.
* =============================================================================
*/
/// <amd-module name="@tensorflow/tfjs-layers/dist/exports" />
/**
* Exported functions.
*/
import { BaseCallbackConstructor } from './base_callbacks';
import { ContainerArgs } from './engine/container';
import { InputConfig } from './engine/input_layer';
import { SymbolicTensor } from './engine/topology';
import { LayersModel } from './engine/training';
import { Sequential, SequentialArgs } from './models';
export { loadLayersModel } from './models';
/**
* A model is a data structure that consists of `Layers` and defines inputs
* and outputs.
*
* The key difference between `tf.model` and `tf.sequential` is that
* `tf.model` is more generic, supporting an arbitrary graph (without
* cycles) of layers. `tf.sequential` is less generic and supports only a linear
* stack of layers.
*
* When creating a `tf.LayersModel`, specify its input(s) and output(s). Layers
* are used to wire input(s) to output(s).
*
* For example, the following code snippet defines a model consisting of
* two `dense` layers, with 10 and 4 units, respectively.
*
* ```js
* // Define input, which has a size of 5 (not including batch dimension).
* const input = tf.input({shape: [5]});
*
* // First dense layer uses relu activation.
* const denseLayer1 = tf.layers.dense({units: 10, activation: 'relu'});
* // Second dense layer uses softmax activation.
* const denseLayer2 = tf.layers.dense({units: 4, activation: 'softmax'});
*
* // Obtain the output symbolic tensor by applying the layers on the input.
* const output = denseLayer2.apply(denseLayer1.apply(input));
*
* // Create the model based on the inputs.
* const model = tf.model({inputs: input, outputs: output});
*
* // The model can be used for training, evaluation and prediction.
* // For example, the following line runs prediction with the model on
* // some fake data.
* model.predict(tf.ones([2, 5])).print();
* ```
* See also:
* `tf.sequential`, `tf.loadLayersModel`.
*
* @doc {heading: 'Models', subheading: 'Creation'}
*/
export declare function model(args: ContainerArgs): LayersModel;
/**
* Creates a `tf.Sequential` model. A sequential model is any model where the
* outputs of one layer are the inputs to the next layer, i.e. the model
* topology is a simple 'stack' of layers, with no branching or skipping.
*
* This means that the first layer passed to a `tf.Sequential` model should have
* a defined input shape. What that means is that it should have received an
* `inputShape` or `batchInputShape` argument, or for some type of layers
* (recurrent, Dense...) an `inputDim` argument.
*
* The key difference between `tf.model` and `tf.sequential` is that
* `tf.sequential` is less generic, supporting only a linear stack of layers.
* `tf.model` is more generic and supports an arbitrary graph (without
* cycles) of layers.
*
* Examples:
*
* ```js
* const model = tf.sequential();
*
* // First layer must have an input shape defined.
* model.add(tf.layers.dense({units: 32, inputShape: [50]}));
* // Afterwards, TF.js does automatic shape inference.
* model.add(tf.layers.dense({units: 4}));
*
* // Inspect the inferred shape of the model's output, which equals
* // `[null, 4]`. The 1st dimension is the undetermined batch dimension; the
* // 2nd is the output size of the model's last layer.
* console.log(JSON.stringify(model.outputs[0].shape));
* ```
*
* It is also possible to specify a batch size (with potentially undetermined
* batch dimension, denoted by "null") for the first layer using the
* `batchInputShape` key. The following example is equivalent to the above:
*
* ```js
* const model = tf.sequential();
*
* // First layer must have a defined input shape
* model.add(tf.layers.dense({units: 32, batchInputShape: [null, 50]}));
* // Afterwards, TF.js does automatic shape inference.
* model.add(tf.layers.dense({units: 4}));
*
* // Inspect the inferred shape of the model's output.
* console.log(JSON.stringify(model.outputs[0].shape));
* ```
*
* You can also use an `Array` of already-constructed `Layer`s to create
* a `tf.Sequential` model:
*
* ```js
* const model = tf.sequential({
* layers: [tf.layers.dense({units: 32, inputShape: [50]}),
* tf.layers.dense({units: 4})]
* });
* console.log(JSON.stringify(model.outputs[0].shape));
* ```
*
* @doc {heading: 'Models', subheading: 'Creation'}
*/
export declare function sequential(config?: SequentialArgs): Sequential;
/**
* Used to instantiate an input to a model as a `tf.SymbolicTensor`.
*
* Users should call the `input` factory function for
* consistency with other generator functions.
*
* Example:
*
* ```js
* // Defines a simple logistic regression model with 32 dimensional input
* // and 3 dimensional output.
* const x = tf.input({shape: [32]});
* const y = tf.layers.dense({units: 3, activation: 'softmax'}).apply(x);
* const model = tf.model({inputs: x, outputs: y});
* model.predict(tf.ones([2, 32])).print();
* ```
*
* Note: `input` is only necessary when using `model`. When using
* `sequential`, specify `inputShape` for the first layer or use `inputLayer`
* as the first layer.
*
* @doc {heading: 'Models', subheading: 'Inputs'}
*/
export declare function input(config: InputConfig): SymbolicTensor;
export declare function registerCallbackConstructor(verbosityLevel: number, callbackConstructor: BaseCallbackConstructor): void;