The `jax.experimental.stax` and `jax.experimental.optimizers` modules are standalone examples libraries. By contrast, the remaining modules in `jax.experimental` are experimental features of the JAX core system. This change moves the two example libraries, and the README that describes them, to `jax.example_libraries` to reflect this distinction.
PiperOrigin-RevId: 404405186
* Make check_dtypes, atol, and rtol keyword-only arguments in jax.test_util APIs.
Default to check_dtypes=True.
Remove explicit usages of check_dtypes=True from tests. This mostly just removes visual noise from tests. Testing for exact type equality is the sensible default, although there are cases where opting out makes sense.
No functional changes intended.
* Fix a number of lax reference implementations to preserve types.
* Change scalar promotion rules to prefer array types over scalar types.
Currently JAX does not treat Python scalars specially during type promotion. This means that, for example:
`1. + np.array([...], np.float32)`
ends up as an array of type np.float64. The `1.` is promoted to a default type (here np.float64), and the type promotion of a np.float64 and an np.float32 is an np.float64. This is unlike classic NumPy, which treats scalars specially during type promotion, in particular, preferring the type of an array over the type of a scalar.
This change adds a notion of weak_type to JAX avals. During type promotion, we prefer non-weak types, i.e., the type of the array in the example above, ignoring the type of the scalar.
In contexts where a Python scalar is to be promoted to a NumPy value, a default type is used (e.g., `np.float_`). This change also makes it possible to use 32-bit default types that differ from NumPy's default types. The JAX test suite passes with 32-bit default types. However, we do not yet enable this change or expose it in the API.
* Change test tolerance logic not to choose tolerance values based on flags (in particular, --jax_enable_x64).
We would like to move away from having global flags to enable 64-bit mode. We therefore need other methods to select test tolerances. Instead, use a per-type default tolerance, and allow tests to pass per-type dictionaries of tolerances as atol and rtol values. Fix up a number of tolerances to make tests pass.
* Fix test tolerances.
* Fix dtype canonicalization for test tolerances.
* Relax core test_vjp tolerance.
* add more optimizers numerical tests
* update examples and readme with new optimziers api
* add device_values parameter to xla_call
* change optimizers.py to flatten trees and subtrees
* remove tree_map2, tree_multimap2, tree_mimomap, tree_prefixmap
* add optimizer tests: DeviceTuples and error msgs
* make the device_values arg to jit private
