Build()
build() is a Keras method that creates a layer’s or model’s state, including weights, after the input shape is known.
Deep Learning with Python, Third Edition
A Keras model method that creates weights for a model when given an input shape before the model is first called.
- How it is used
- Configures layers and models before their first data call when input shapes are known.
- How deep it goes
- Explains shape-dependent weight creation and custom-layer structure, but does not develop broader Keras lifecycle internals.
- Examples
- Uses a custom SimpleDense layer, a two-layer Sequential model, explicit input shapes, weight listings, and summary output.
- What you can do after
- Operate/configure Keras models, create weights from input shapes, and inspect architectures with summary().
Read how Deep Learning with Python, Third Edition explains build() →
Deep Learning with R, Third Edition
The Keras build method creates a layer's state after receiving the shape of its input.
- How it is used
- Creates shape-dependent layer state before call() performs the forward computation.
- How deep it goes
- Explains lazy construction, input-shape-dependent weights, explicit model building, and summary inspection without descending into weight initialization internals.
- Examples
- Uses a custom SimpleDense layer, a (2, 784) input tensor, and Sequential models with explicit or automatic building.
- What you can do after
- Builds custom Keras layers and debugs model weights, output shapes, and summaries before training.
Read how Deep Learning with R, Third Edition explains build() →
Related concepts
- automatic shape inferenceused by · Automatic shape inference is the process of determining a layer's input and output shapes from the shapes of tensors supplied to it.
- Sequential modelused by · A sequential model is a neural-network model comprising a linear, ordered stack of layers through which data flows from input to output.
- call()equivalent to · call() is the Keras method that defines the forward computation a layer or model performs on its inputs.
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