Configure a Keras backend

Usage

use_backend(backend, gpu = NA)

Arguments

backend: string, can be "tensorflow", "jax", "numpy", or "torch".
gpu: bool, whether to use the GPU. If NA (default), it will attempt to detect GPU availability on Linux. On macOS and Windows it defaults to FALSE.

Value

Called primarily for side effects. Returns the provided backend, invisibly.

Details

These functions allow configuring which backend keras will use. Note that only one backend can be configured at a time.

The function should be called after library(keras3) and before calling other functions within the package (see below for an example).

Note that macOS packages like tensorflow-metal and jax-metal that purportedly enabled GPU usage on M-series macs all are currently broken and seemingly abandoned.

There is experimental support for changing the backend after keras has initialized with config_set_backend(). Usage of config_set_backend is generally not recommended for regular workflow—restarting the R session is the only reliable way to change the backend.

library(keras3)
use_backend("tensorflow")