jax.numpy.argmax

jax.numpy.argmax(a, axis=None, out=None, keepdims=None)

Return the index of the maximum value of an array.

JAX implementation of numpy.argmax().

Parameters:

• a (ArrayLike) – input array

• axis (int | None | None) – optional integer specifying the axis along which to find the maximum value. If axis is not specified, a will be flattened.

• out (None | None) – unused by JAX

• keepdims (bool | None | None) – if True, then return an array with the same number of dimensions as a.

Returns:

an array containing the index of the maximum value along the specified axis.

Return type:

Array

See also

• jax.numpy.argmin(): return the index of the minimum value.

• jax.numpy.nanargmax(): compute argmax while ignoring NaN values.

Examples

>>> x = jnp.array([1, 3, 5, 4, 2])
>>> jnp.argmax(x)
Array(2, dtype=int32)

>>> x = jnp.array([[1, 3, 2],
...                [5, 4, 1]])
>>> jnp.argmax(x, axis=1)
Array([1, 0], dtype=int32)

>>> jnp.argmax(x, axis=1, keepdims=True)
Array([[1],
       [0]], dtype=int32)