docstr: Tests the autoregresive self-attention receptive field.
docstr_tok: ["Tests","the","autoregresive","self-attention","receptive","field","."]
code: def test_autoregresive_receptive_field_1d(self):
      """Tests the autoregresive self-attention receptive field."""
      rng = random.key(0)
      rng1, rng2 = random.split(rng, num=2)
  
      length = 10
      dim = 1
      num_heads = 1
      input_shape = (1, length, dim)
      inputs = random.normal(rng2, input_shape)
  
      module = nn.MultiHeadDotProductAttention(
          num_heads=num_heads,
          kernel_init=jax.nn.initializers.ones,
          deterministic=False,
      )
  
      initial_vars = module.init(rng1, inputs)
      causal_mask = nn.attention.make_causal_mask(
          jnp.ones(input_shape[:-1])
      )
  
      def model_loss(inputs, pos):
          out = module.apply(initial_vars, inputs, mask=causal_mask)
          assert out.shape == input_shape
          assert len(out.shape) == 3
          return out[0, pos, :].sum()
  
      grad_fn = jax.jit(jax.grad(model_loss))
  
      def get_receptive_field_1d(pos):
          g = grad_fn(inputs, pos)[0, :, :]
          return jnp.any(
              (jnp.abs(g) > 1e-5).astype(jnp.uint32), axis=-1
          )
  
      for i in range(length):
          deps = get_receptive_field_1d(i)
          assert (deps[:i] == 1).all(), (
              "Receptive Field Error: Some of the "
              "previous postions are not reachable "
              "in autoregressive self-attention."
          )
          if i != length - 1:
              k = i + 1
              assert (deps[k:] == 0).all(), (
                  "Receptive Field Error: Some of the "
                  "future postions are reachable in "
                  "autoregressive self-attention."
              )
  
imports: import jax
  import jax.numpy
  import numpy
  from absl.testing import absltest, parameterized
  from jax import lax, random
  from jax.nn import initializers
  from flax import errors, jax_utils
  from flax import linen
  from flax.core import pop
label_desc: Use image node_id 9 for calling the AttentionTest obj's underlying member method code with example usage: obj.test_autoregresive_receptive_field_1d() and returns: out, jnp