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@@ -12,7 +12,7 @@ JAX bindings and native implementations of differentiable trust region projectio
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- Multiple projection types:
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- KL (Kullback-Leibler divergence)
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- Wasserstein (only diagonal covariance)
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- Frobenius (wip, not tested)
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- Frobenius (wip, problem with cov projections)
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- Identity (no projection)
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- Support for both diagonal and full covariance Gaussians (induced from cholesky decomposition)
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- Contextual and non-contextual standard deviations (non-contextual means all standard deviations in batch are expected to be the same)
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@@ -65,9 +65,7 @@ pytest tests/test_projections.py
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*Note*: The test suite verifies:
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1. All projections run without errors and maintain basic properties (shapes, positive definiteness)
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2. KL bounds are actually (approximately) met for:
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- KL projection (both diagonal and full covariance)
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- Wasserstein projection (diagonal covariance only)
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2. KL bounds are actually (approximately) met for true KL projection (both diagonal and full covariance)
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3. Gradients can be computed through all projections:
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- Both through projection operation and trust region loss
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- Gradients have correct shapes and are finite
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@@ -1,6 +1,8 @@
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from abc import ABC, abstractmethod
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from typing import Dict
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import jax
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import jax.numpy as jnp
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from functools import partial
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class BaseProjection(ABC):
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def __init__(self, trust_region_coeff: float = 1.0, mean_bound: float = 0.01,
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@@ -8,22 +10,48 @@ class BaseProjection(ABC):
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self.trust_region_coeff = trust_region_coeff
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self.mean_bound = mean_bound
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self.cov_bound = cov_bound
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self.full_cov = full_cov
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self.contextual_std = contextual_std
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self.full_cov = full_cov
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@abstractmethod
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def project(self, policy_params: Dict[str, jnp.ndarray],
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old_policy_params: Dict[str, jnp.ndarray]) -> Dict[str, jnp.ndarray]:
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"""Project policy parameters.
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"""Project parameters to satisfy trust region constraints."""
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raise NotImplementedError
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@abstractmethod
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def get_trust_region_loss(self, policy_params: Dict[str, jnp.ndarray],
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proj_policy_params: Dict[str, jnp.ndarray]) -> jnp.ndarray:
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"""Compute trust region loss between original and projected parameters."""
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raise NotImplementedError
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@partial(jax.jit, static_argnames=('self'))
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def _mean_projection(self, mean: jnp.ndarray, old_mean: jnp.ndarray,
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mean_part: jnp.ndarray) -> jnp.ndarray:
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"""Project mean based on the Mahalanobis objective and trust region.
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Args:
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policy_params: Dictionary with:
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- 'loc': mean parameters (batch_size, dim)
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- 'scale': standard deviations (batch_size, dim) if full_cov=False
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- 'scale_tril': Cholesky factor (batch_size, dim, dim) if full_cov=True
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old_policy_params: Same format as policy_params
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mean: Current mean vectors
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old_mean: Old mean vectors
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mean_part: Mahalanobis/Euclidean distance between the two mean vectors
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Returns:
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Projected mean that satisfies the trust region
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"""
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pass
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mask = mean_part > self.mean_bound
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omega = jnp.ones_like(mean_part)
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omega = jnp.where(mask, jnp.sqrt(mean_part / self.mean_bound) - 1., omega)
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omega = jnp.maximum(-omega, omega)[..., None]
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# Use matrix operations instead of boolean indexing
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m = (mean + omega * old_mean) / (1. + omega + 1e-16)
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mask_matrix = mask[..., None].astype(mean.dtype)
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return mask_matrix * m + (1 - mask_matrix) * mean
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def _cov_projection(self, scale_or_tril: jnp.ndarray, old_scale_or_tril: jnp.ndarray,
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cov_part: jnp.ndarray) -> jnp.ndarray:
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"""Project covariance parameters."""
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raise NotImplementedError
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def _calc_covariance(self, params: Dict[str, jnp.ndarray]) -> jnp.ndarray:
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"""Convert scale representation to covariance matrix."""
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@@ -1,6 +1,8 @@
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import jax.numpy as jnp
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from .base_projection import BaseProjection
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from typing import Dict
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import jax
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from functools import partial
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class FrobeniusProjection(BaseProjection):
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def __init__(self, trust_region_coeff: float = 1.0, mean_bound: float = 0.01,
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@@ -46,6 +48,7 @@ class FrobeniusProjection(BaseProjection):
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else:
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return {"loc": proj_mean, "scale": scale_or_tril}
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@partial(jax.jit, static_argnames=('self'))
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def get_trust_region_loss(self, policy_params: Dict[str, jnp.ndarray],
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proj_policy_params: Dict[str, jnp.ndarray]) -> jnp.ndarray:
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mean = policy_params["loc"]
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@@ -59,46 +62,53 @@ class FrobeniusProjection(BaseProjection):
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return (mean_diff + cov_diff).mean() * self.trust_region_coeff
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@partial(jax.jit, static_argnames=('self'))
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def _gaussian_frobenius(self, p, q):
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mean, cov = p
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old_mean, old_cov = q
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if self.scale_prec:
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prec_old = jnp.linalg.inv(old_cov)
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mean_part = jnp.sum(jnp.matmul(mean - old_mean, prec_old) * (mean - old_mean), axis=-1)
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cov_part = jnp.sum(prec_old * cov, axis=(-2, -1)) - jnp.log(jnp.linalg.det(jnp.matmul(prec_old, cov))) - mean.shape[-1]
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# Mahalanobis distance for mean
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diff = mean - old_mean
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if old_cov.ndim == mean.ndim: # diagonal case
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mean_part = jnp.sum(jnp.square(diff / old_cov), axis=-1)
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else:
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solved = jax.scipy.linalg.solve_triangular(
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old_cov, diff[..., None], lower=True
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)
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mean_part = jnp.sum(jnp.square(solved.squeeze(-1)), axis=-1)
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else:
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mean_part = jnp.sum(jnp.square(mean - old_mean), axis=-1)
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cov_part = jnp.sum(jnp.square(cov - old_cov), axis=(-2, -1))
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# Frobenius norm for covariance
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if cov.ndim == mean.ndim: # diagonal case
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diff = old_cov - cov
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cov_part = jnp.sum(jnp.square(diff), axis=-1)
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else:
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diff = jnp.matmul(old_cov, jnp.swapaxes(old_cov, -1, -2)) - \
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jnp.matmul(cov, jnp.swapaxes(cov, -1, -2))
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cov_part = jnp.sum(jnp.square(diff), axis=(-2, -1))
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return mean_part, cov_part
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def _mean_projection(self, mean: jnp.ndarray, old_mean: jnp.ndarray,
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mean_part: jnp.ndarray) -> jnp.ndarray:
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diff = mean - old_mean
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norm = jnp.sqrt(mean_part)
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return jnp.where(norm > self.mean_bound,
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old_mean + diff * self.mean_bound / norm[..., None],
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mean)
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def _cov_projection(self, cov: jnp.ndarray, old_cov: jnp.ndarray,
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cov_part: jnp.ndarray) -> jnp.ndarray:
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batch_shape = cov.shape[:-2]
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batch_shape = cov.shape[:-2] if cov.ndim > 2 else cov.shape[:-1]
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cov_mask = cov_part > self.cov_bound
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eta = jnp.ones(batch_shape, dtype=cov.dtype)
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eta = jnp.where(cov_mask,
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jnp.sqrt(cov_part / self.cov_bound) - 1.,
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eta)
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jnp.sqrt(cov_part / self.cov_bound) - 1.,
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eta)
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eta = jnp.maximum(-eta, eta)
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if self.full_cov:
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new_cov = (cov + jnp.einsum('...,...ij->...ij', eta, old_cov)) / (1. + eta + 1e-16)[..., None, None]
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new_cov = (cov + jnp.einsum('...,...ij->...ij', eta, old_cov)) / \
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(1. + eta + 1e-16)[..., None, None]
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mask_matrix = cov_mask[..., None, None].astype(cov.dtype)
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proj_cov = mask_matrix * new_cov + (1 - mask_matrix) * cov
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return jnp.linalg.cholesky(proj_cov)
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else:
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# For diagonal case, simple broadcasting
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new_cov = (cov + eta[..., None] * old_cov) / (1. + eta + 1e-16)[..., None]
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proj_cov = jnp.where(cov_mask[..., None] if not self.full_cov else cov_mask[..., None, None],
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new_cov, cov)
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return proj_cov
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mask_matrix = cov_mask[..., None].astype(cov.dtype)
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return mask_matrix * jnp.sqrt(new_cov) + (1 - mask_matrix) * cov
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@@ -1,6 +1,8 @@
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import jax.numpy as jnp
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from .base_projection import BaseProjection
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from typing import Dict
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import jax
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from functools import partial
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class IdentityProjection(BaseProjection):
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def __init__(self, trust_region_coeff: float = 1.0, mean_bound: float = 0.01,
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@@ -8,10 +10,12 @@ class IdentityProjection(BaseProjection):
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super().__init__(trust_region_coeff=trust_region_coeff, mean_bound=mean_bound,
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cov_bound=cov_bound, contextual_std=contextual_std, full_cov=full_cov)
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@partial(jax.jit, static_argnames=('self'))
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def project(self, policy_params: Dict[str, jnp.ndarray],
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old_policy_params: Dict[str, jnp.ndarray]) -> Dict[str, jnp.ndarray]:
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return policy_params
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@partial(jax.jit, static_argnames=('self'))
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def get_trust_region_loss(self, policy_params: Dict[str, jnp.ndarray],
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proj_policy_params: Dict[str, jnp.ndarray]) -> jnp.ndarray:
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return jnp.array(0.0)
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+88
-60
@@ -13,6 +13,24 @@ from .exception_projection import makeExceptionProjection
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MAX_EVAL = 1000
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# Cache for projection operators
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_diag_proj_op = None
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_full_proj_op = None
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def _get_diag_proj_op(batch_shape, dim):
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global _diag_proj_op
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if _diag_proj_op is None:
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_diag_proj_op = cpp_projection.BatchedDiagCovOnlyProjection(
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batch_shape, dim, max_eval=MAX_EVAL)
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return _diag_proj_op
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def _get_full_proj_op(batch_shape, dim):
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global _full_proj_op
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if _full_proj_op is None:
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_full_proj_op = cpp_projection.BatchedCovOnlyProjection(
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batch_shape, dim, max_eval=MAX_EVAL)
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return _full_proj_op
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class KLProjection(BaseProjection):
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"""KL divergence-based projection for Gaussian policies.
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@@ -68,13 +86,25 @@ class KLProjection(BaseProjection):
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else:
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return {"loc": proj_mean, "scale": proj_scale_or_tril}
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@partial(jax.jit, static_argnames=('self'))
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def get_trust_region_loss(self, policy_params: Dict[str, jnp.ndarray],
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proj_policy_params: Dict[str, jnp.ndarray]) -> jnp.ndarray:
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mean, scale_or_tril = policy_params["loc"], policy_params["scale"]
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proj_mean, proj_scale_or_tril = proj_policy_params["loc"], proj_policy_params["scale"]
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"""Compute trust region loss between original and projected parameters."""
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# Get the right scale parameter based on full_cov
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mean = policy_params["loc"]
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proj_mean = proj_policy_params["loc"]
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if self.full_cov:
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scale_or_tril = policy_params["scale_tril"]
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proj_scale_or_tril = proj_policy_params["scale_tril"]
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else:
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scale_or_tril = policy_params["scale"]
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proj_scale_or_tril = proj_policy_params["scale"]
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kl = sum(self._gaussian_kl((mean, scale_or_tril), (proj_mean, proj_scale_or_tril)))
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return jnp.mean(kl) * self.trust_region_coeff
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@partial(jax.jit, static_argnames=('self'))
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def _gaussian_kl(self, p: Tuple[jnp.ndarray, jnp.ndarray],
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q: Tuple[jnp.ndarray, jnp.ndarray]) -> Tuple[jnp.ndarray, jnp.ndarray]:
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mean, scale_or_tril = p
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@@ -99,6 +129,7 @@ class KLProjection(BaseProjection):
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return maha_part, cov_part
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@partial(jax.jit, static_argnames=('self'))
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def _maha(self, x: jnp.ndarray, y: jnp.ndarray, scale_or_tril: jnp.ndarray) -> jnp.ndarray:
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diff = x - y
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if self.full_cov:
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@@ -109,21 +140,17 @@ class KLProjection(BaseProjection):
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else:
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return jnp.sum(jnp.square(diff / scale_or_tril), axis=-1)
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@partial(jax.jit, static_argnames=('self'))
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def _log_determinant(self, scale_or_tril: jnp.ndarray) -> jnp.ndarray:
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if self.full_cov:
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return 2 * jnp.sum(jnp.log(jnp.diagonal(scale_or_tril, axis1=-2, axis2=-1)), axis=-1)
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else:
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return 2 * jnp.sum(jnp.log(scale_or_tril), axis=-1)
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@partial(jax.jit, static_argnames=('self'))
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def _batched_trace_square(self, x: jnp.ndarray) -> jnp.ndarray:
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return jnp.sum(x ** 2, axis=(-2, -1))
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def _mean_projection(self, mean: jnp.ndarray, old_mean: jnp.ndarray,
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mean_part: jnp.ndarray) -> jnp.ndarray:
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return old_mean + (mean - old_mean) * jnp.sqrt(
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self.mean_bound / (mean_part + 1e-8)
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)[..., None]
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def _cov_projection(self, scale_or_tril: jnp.ndarray, old_scale_or_tril: jnp.ndarray, cov_part: jnp.ndarray) -> jnp.ndarray:
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if self.full_cov:
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cov = jnp.matmul(scale_or_tril, jnp.swapaxes(scale_or_tril, -1, -2))
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@@ -133,14 +160,13 @@ class KLProjection(BaseProjection):
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old_cov = old_scale_or_tril ** 2
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mask = cov_part > self.cov_bound
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proj_scale_or_tril = jnp.zeros_like(scale_or_tril)
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proj_scale_or_tril = jnp.where(~mask, scale_or_tril, proj_scale_or_tril)
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proj_scale_or_tril = scale_or_tril # Start with original scale
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if mask.any():
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if self.full_cov:
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proj_cov = project_full_covariance(cov, scale_or_tril, old_scale_or_tril, self.cov_bound)
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is_invalid = jnp.isnan(proj_cov.mean(axis=(-2, -1))) & mask
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proj_scale_or_tril = jnp.where(is_invalid, old_scale_or_tril, proj_scale_or_tril)
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is_invalid = jnp.isnan(proj_cov.mean(axis=(-2, -1)))
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proj_scale_or_tril = jnp.where(is_invalid[..., None, None], old_scale_or_tril, scale_or_tril)
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mask = mask & ~is_invalid
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chol = jnp.linalg.cholesky(proj_cov)
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proj_scale_or_tril = jnp.where(mask[..., None, None], chol, proj_scale_or_tril)
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@@ -148,10 +174,12 @@ class KLProjection(BaseProjection):
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proj_cov = project_diag_covariance(cov, old_cov, self.cov_bound)
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is_invalid = (jnp.isnan(proj_cov.mean(axis=-1)) |
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jnp.isinf(proj_cov.mean(axis=-1)) |
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(proj_cov.min(axis=-1) < 0)) & mask
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proj_scale_or_tril = jnp.where(is_invalid, old_scale_or_tril, proj_scale_or_tril)
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(proj_cov.min(axis=-1) < 0))
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proj_scale_or_tril = jnp.where(is_invalid[..., None], old_scale_or_tril, scale_or_tril)
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mask = mask & ~is_invalid
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proj_scale_or_tril = jnp.where(mask[..., None], jnp.sqrt(proj_cov), proj_scale_or_tril)
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proj_scale_or_tril = jnp.where(mask[..., None], jnp.sqrt(proj_cov), scale_or_tril)
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else:
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proj_scale_or_tril = scale_or_tril
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return proj_scale_or_tril
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@@ -166,6 +194,49 @@ class KLProjection(BaseProjection):
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if key not in policy_params or key not in old_policy_params:
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raise KeyError(f"Missing required key '{key}' in policy parameters")
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@partial(jax.custom_vjp, nondiff_argnums=(2,))
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def project_diag_covariance(cov, old_cov, eps_cov):
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"""JAX wrapper for C++ diagonal covariance projection"""
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batch_shape = cov.shape[0]
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dim = cov.shape[-1]
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cov_np = np.asarray(cov)
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old_cov_np = np.asarray(old_cov)
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eps = eps_cov * np.ones(batch_shape, dtype=old_cov_np.dtype)
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p_op = _get_diag_proj_op(batch_shape, dim)
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try:
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proj_cov = p_op.forward(eps, old_cov_np, cov_np)
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except:
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proj_cov = cov_np # Return input on failure
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return jnp.array(proj_cov)
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def project_diag_covariance_fwd(cov, old_cov, eps_cov):
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y = project_diag_covariance(cov, old_cov, eps_cov)
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return y, (cov, old_cov)
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def project_diag_covariance_bwd(eps_cov, res, g):
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cov, old_cov = res
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# Convert to numpy for C++ backward pass
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g_np = np.asarray(g)
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batch_shape = g_np.shape[0]
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dim = g_np.shape[-1]
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# Get C++ projection operator
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p_op = _get_diag_proj_op(batch_shape, dim)
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# Run C++ backward pass
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grad_cov = p_op.backward(g_np)
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# Convert back to JAX array
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||||
return jnp.array(grad_cov), None
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# Register VJP rule for diagonal covariance projection
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project_diag_covariance.defvjp(project_diag_covariance_fwd, project_diag_covariance_bwd)
|
||||
|
||||
@partial(jax.custom_vjp, nondiff_argnums=(3,))
|
||||
def project_full_covariance(cov, chol, old_chol, eps_cov):
|
||||
"""JAX wrapper for C++ full covariance projection"""
|
||||
@@ -179,7 +250,7 @@ def project_full_covariance(cov, chol, old_chol, eps_cov):
|
||||
eps = eps_cov * np.ones(batch_shape)
|
||||
|
||||
# Create C++ projection operator directly
|
||||
p_op = cpp_projection.BatchedCovOnlyProjection(batch_shape, dim, max_eval=MAX_EVAL)
|
||||
p_op = _get_full_proj_op(batch_shape, dim)
|
||||
|
||||
# Run C++ projection
|
||||
proj_cov = p_op.forward(eps, old_chol_np, chol_np, cov_np)
|
||||
@@ -203,7 +274,7 @@ def project_full_covariance_bwd(eps_cov, res, g):
|
||||
dim = g_np.shape[-1]
|
||||
|
||||
# Get C++ projection operator
|
||||
p_op = cpp_projection.BatchedCovOnlyProjection(batch_shape, dim, max_eval=MAX_EVAL)
|
||||
p_op = _get_full_proj_op(batch_shape, dim)
|
||||
|
||||
# Run C++ backward pass
|
||||
grad_cov = p_op.backward(g_np)
|
||||
@@ -214,48 +285,5 @@ def project_full_covariance_bwd(eps_cov, res, g):
|
||||
# Register VJP rule for full covariance projection
|
||||
project_full_covariance.defvjp(project_full_covariance_fwd, project_full_covariance_bwd)
|
||||
|
||||
@partial(jax.custom_vjp, nondiff_argnums=(2,))
|
||||
def project_diag_covariance(cov, old_cov, eps_cov):
|
||||
"""JAX wrapper for C++ diagonal covariance projection"""
|
||||
# Convert JAX arrays to numpy for C++ function
|
||||
cov_np = np.asarray(cov)
|
||||
old_cov_np = np.asarray(old_cov)
|
||||
batch_shape = cov_np.shape[0]
|
||||
dim = cov_np.shape[-1]
|
||||
eps = eps_cov * np.ones(batch_shape)
|
||||
|
||||
# Create C++ projection operator directly
|
||||
p_op = cpp_projection.BatchedDiagCovOnlyProjection(batch_shape, dim, max_eval=MAX_EVAL)
|
||||
|
||||
# Run C++ projection
|
||||
proj_cov = p_op.forward(eps, old_cov_np, cov_np)
|
||||
|
||||
# Convert back to JAX array
|
||||
return jnp.array(proj_cov)
|
||||
|
||||
def project_diag_covariance_fwd(cov, old_cov, eps_cov):
|
||||
y = project_diag_covariance(cov, old_cov, eps_cov)
|
||||
return y, (cov, old_cov)
|
||||
|
||||
def project_diag_covariance_bwd(eps_cov, res, g):
|
||||
cov, old_cov = res
|
||||
|
||||
# Convert to numpy for C++ backward pass
|
||||
g_np = np.asarray(g)
|
||||
batch_shape = g_np.shape[0]
|
||||
dim = g_np.shape[-1]
|
||||
|
||||
# Get C++ projection operator
|
||||
p_op = cpp_projection.BatchedDiagCovOnlyProjection(batch_shape, dim, max_eval=MAX_EVAL)
|
||||
|
||||
# Run C++ backward pass
|
||||
grad_cov = p_op.backward(g_np)
|
||||
|
||||
# Convert back to JAX array
|
||||
return jnp.array(grad_cov), None
|
||||
|
||||
# Register VJP rule for diagonal covariance projection
|
||||
project_diag_covariance.defvjp(project_diag_covariance_fwd, project_diag_covariance_bwd)
|
||||
|
||||
if not cpp_projection_available:
|
||||
KLProjection = makeExceptionProjection("ITPAL (C++ library) is not available. Please install the C++ library to use this projection.")
|
||||
@@ -1,7 +1,10 @@
|
||||
import jax.numpy as jnp
|
||||
from .base_projection import BaseProjection
|
||||
from typing import Dict, Tuple
|
||||
import jax
|
||||
from functools import partial
|
||||
|
||||
@jax.jit
|
||||
def scale_tril_to_sqrt(scale_tril: jnp.ndarray) -> jnp.ndarray:
|
||||
"""
|
||||
'Converts' scale_tril to scale_sqrt.
|
||||
@@ -22,7 +25,8 @@ class WassersteinProjection(BaseProjection):
|
||||
|
||||
def project(self, policy_params: Dict[str, jnp.ndarray],
|
||||
old_policy_params: Dict[str, jnp.ndarray]) -> Dict[str, jnp.ndarray]:
|
||||
assert not self.full_cov, "Wasserstein projection only supports diagonal covariance"
|
||||
if self.full_cov:
|
||||
print("Warning: Wasserstein projection with full covariance is wip, we recommend using diagonal covariance instead.")
|
||||
|
||||
mean = policy_params["loc"] # shape: (batch_size, dim)
|
||||
old_mean = old_policy_params["loc"]
|
||||
@@ -50,6 +54,7 @@ class WassersteinProjection(BaseProjection):
|
||||
|
||||
return {"loc": proj_mean, "scale": proj_scale}
|
||||
|
||||
@partial(jax.jit, static_argnames=('self'))
|
||||
def get_trust_region_loss(self, policy_params: Dict[str, jnp.ndarray],
|
||||
proj_policy_params: Dict[str, jnp.ndarray]) -> jnp.ndarray:
|
||||
mean = policy_params["loc"]
|
||||
@@ -63,37 +68,51 @@ class WassersteinProjection(BaseProjection):
|
||||
w2 = mean_part + cov_part
|
||||
return w2.mean() * self.trust_region_coeff
|
||||
|
||||
def _mean_projection(self, mean: jnp.ndarray, old_mean: jnp.ndarray,
|
||||
mean_part: jnp.ndarray) -> jnp.ndarray:
|
||||
diff = mean - old_mean
|
||||
norm = jnp.sqrt(mean_part)
|
||||
return jnp.where(norm > self.mean_bound,
|
||||
old_mean + diff * self.mean_bound / norm[..., None],
|
||||
mean)
|
||||
|
||||
def _scale_projection(self, scale: jnp.ndarray, old_scale: jnp.ndarray,
|
||||
scale_part: jnp.ndarray) -> jnp.ndarray:
|
||||
"""Project scale parameters (standard deviations for diagonal case)"""
|
||||
diff = scale - old_scale
|
||||
norm = jnp.sqrt(scale_part)
|
||||
"""Project scale parameters using multiplicative update.
|
||||
|
||||
if scale.ndim == 2: # Batched scale
|
||||
norm = norm[..., None]
|
||||
Args:
|
||||
scale: Current scale/sqrt of covariance
|
||||
old_scale: Previous scale/sqrt of covariance
|
||||
scale_part: W2 distance between scales
|
||||
|
||||
return jnp.where(norm > self.cov_bound,
|
||||
old_scale + diff * self.cov_bound / norm,
|
||||
scale)
|
||||
Returns:
|
||||
Projected scale that satisfies the trust region constraint
|
||||
"""
|
||||
# Check if projection needed
|
||||
cov_mask = scale_part > self.cov_bound
|
||||
|
||||
def _gaussian_wasserstein(self, p, q):
|
||||
# Compute eta (multiplier for the update)
|
||||
batch_shape = scale.shape[:-2] if scale.ndim > 2 else scale.shape[:-1]
|
||||
eta = jnp.ones(batch_shape, dtype=scale.dtype)
|
||||
eta = jnp.where(cov_mask,
|
||||
jnp.sqrt(scale_part / self.cov_bound) - 1.,
|
||||
eta)
|
||||
eta = jnp.maximum(-eta, eta)
|
||||
|
||||
# Multiplicative update with matrix operations
|
||||
if scale.ndim > 2: # Full covariance case
|
||||
new_scale = (scale + jnp.einsum('...,...ij->...ij', eta, old_scale)) / \
|
||||
(1. + eta + 1e-16)[..., None, None]
|
||||
mask_matrix = cov_mask[..., None, None].astype(scale.dtype)
|
||||
return mask_matrix * new_scale + (1 - mask_matrix) * scale
|
||||
else: # Diagonal case
|
||||
new_scale = (scale + eta[..., None] * old_scale) / \
|
||||
(1. + eta + 1e-16)[..., None]
|
||||
mask_matrix = cov_mask[..., None].astype(scale.dtype)
|
||||
return mask_matrix * new_scale + (1 - mask_matrix) * scale
|
||||
|
||||
@staticmethod
|
||||
@jax.jit
|
||||
def _gaussian_wasserstein(p, q):
|
||||
mean, scale = p
|
||||
mean_other, scale_other = q
|
||||
|
||||
# Keep batch dimension by only summing over feature dimension
|
||||
mean_part = jnp.sum(jnp.square(mean - mean_other), axis=-1) # -> (batch_size,)
|
||||
# Euclidean distance for mean part (we're in diagonal case)
|
||||
mean_part = jnp.sum(jnp.square(mean - mean_other), axis=-1)
|
||||
|
||||
if scale.ndim == mean.ndim: # Batched scale
|
||||
cov_part = jnp.sum(scale_other**2 + scale**2 - 2 * scale_other * scale, axis=-1)
|
||||
else: # Non-contextual scale (single scale for all batches)
|
||||
cov_part = jnp.sum(scale_other**2 + scale**2 - 2 * scale_other * scale)
|
||||
# Standard W2 objective for covariance (diagonal case)
|
||||
cov_part = jnp.sum(scale_other**2 + scale**2 - 2 * scale_other * scale, axis=-1)
|
||||
|
||||
return mean_part, cov_part
|
||||
@@ -0,0 +1,50 @@
|
||||
import jax
|
||||
import jax.numpy as jnp
|
||||
import time
|
||||
from itpal_jax import FrobeniusProjection
|
||||
|
||||
def generate_params(key, batch_size, dim):
|
||||
keys = jax.random.split(key, 2)
|
||||
return {
|
||||
"loc": jax.random.normal(keys[0], (batch_size, dim)),
|
||||
"scale": jax.nn.softplus(jax.random.normal(keys[1], (batch_size, dim)))
|
||||
}
|
||||
|
||||
def main():
|
||||
# Test parameters
|
||||
batch_size = 32
|
||||
dim = 8
|
||||
n_iterations = 1000
|
||||
|
||||
# Initialize projector
|
||||
proj = FrobeniusProjection(mean_bound=0.1, cov_bound=0.1, contextual_std=True)
|
||||
|
||||
# Compile function
|
||||
proj_fn = lambda p, op: proj.project(p, op)
|
||||
proj_fn = jax.jit(proj_fn)
|
||||
|
||||
# Generate initial key
|
||||
key = jax.random.PRNGKey(0)
|
||||
|
||||
# Warmup
|
||||
for _ in range(10):
|
||||
key, subkey1, subkey2 = jax.random.split(key, 3)
|
||||
params = generate_params(subkey1, batch_size, dim)
|
||||
old_params = generate_params(subkey2, batch_size, dim)
|
||||
proj_fn(params, old_params)
|
||||
|
||||
# Time projections
|
||||
start_time = time.time()
|
||||
for _ in range(n_iterations):
|
||||
key, subkey1, subkey2 = jax.random.split(key, 3)
|
||||
params = generate_params(subkey1, batch_size, dim)
|
||||
old_params = generate_params(subkey2, batch_size, dim)
|
||||
proj_fn(params, old_params)
|
||||
end_time = time.time()
|
||||
|
||||
print(f"Frobenius Projection:")
|
||||
print(f"Average time per projection: {(end_time - start_time) / n_iterations * 1000:.3f} ms")
|
||||
print(f"Total time for {n_iterations} iterations: {end_time - start_time:.3f} s")
|
||||
|
||||
if __name__ == "__main__":
|
||||
main()
|
||||
@@ -0,0 +1,49 @@
|
||||
import jax
|
||||
import jax.numpy as jnp
|
||||
import time
|
||||
from itpal_jax import KLProjection
|
||||
|
||||
def generate_params(key, batch_size, dim):
|
||||
keys = jax.random.split(key, 2)
|
||||
return {
|
||||
"loc": jax.random.normal(keys[0], (batch_size, dim)),
|
||||
"scale": jax.nn.softplus(jax.random.normal(keys[1], (batch_size, dim)))
|
||||
}
|
||||
|
||||
def main():
|
||||
# Test parameters
|
||||
batch_size = 32
|
||||
dim = 8
|
||||
n_iterations = 1000
|
||||
|
||||
# Initialize projector
|
||||
proj = KLProjection(mean_bound=0.1, cov_bound=0.1, contextual_std=True)
|
||||
|
||||
# No JIT for KL projection since it uses C++ backend
|
||||
proj_fn = lambda p, op: proj.project(p, op)
|
||||
|
||||
# Generate initial key
|
||||
key = jax.random.PRNGKey(0)
|
||||
|
||||
# Warmup
|
||||
for _ in range(10):
|
||||
key, subkey1, subkey2 = jax.random.split(key, 3)
|
||||
params = generate_params(subkey1, batch_size, dim)
|
||||
old_params = generate_params(subkey2, batch_size, dim)
|
||||
proj_fn(params, old_params)
|
||||
|
||||
# Time projections
|
||||
start_time = time.time()
|
||||
for _ in range(n_iterations):
|
||||
key, subkey1, subkey2 = jax.random.split(key, 3)
|
||||
params = generate_params(subkey1, batch_size, dim)
|
||||
old_params = generate_params(subkey2, batch_size, dim)
|
||||
proj_fn(params, old_params)
|
||||
end_time = time.time()
|
||||
|
||||
print(f"KL Projection:")
|
||||
print(f"Average time per projection: {(end_time - start_time) / n_iterations * 1000:.3f} ms")
|
||||
print(f"Total time for {n_iterations} iterations: {end_time - start_time:.3f} s")
|
||||
|
||||
if __name__ == "__main__":
|
||||
main()
|
||||
@@ -0,0 +1,50 @@
|
||||
import jax
|
||||
import jax.numpy as jnp
|
||||
import time
|
||||
from itpal_jax import WassersteinProjection
|
||||
|
||||
def generate_params(key, batch_size, dim):
|
||||
keys = jax.random.split(key, 2)
|
||||
return {
|
||||
"loc": jax.random.normal(keys[0], (batch_size, dim)),
|
||||
"scale": jax.nn.softplus(jax.random.normal(keys[1], (batch_size, dim)))
|
||||
}
|
||||
|
||||
def main():
|
||||
# Test parameters
|
||||
batch_size = 32
|
||||
dim = 8
|
||||
n_iterations = 1000
|
||||
|
||||
# Initialize projector
|
||||
proj = WassersteinProjection(mean_bound=0.1, cov_bound=0.1, contextual_std=True)
|
||||
|
||||
# Compile function
|
||||
proj_fn = lambda p, op: proj.project(p, op)
|
||||
proj_fn = jax.jit(proj_fn)
|
||||
|
||||
# Generate initial key
|
||||
key = jax.random.PRNGKey(0)
|
||||
|
||||
# Warmup
|
||||
for _ in range(10):
|
||||
key, subkey1, subkey2 = jax.random.split(key, 3)
|
||||
params = generate_params(subkey1, batch_size, dim)
|
||||
old_params = generate_params(subkey2, batch_size, dim)
|
||||
proj_fn(params, old_params)
|
||||
|
||||
# Time projections
|
||||
start_time = time.time()
|
||||
for _ in range(n_iterations):
|
||||
key, subkey1, subkey2 = jax.random.split(key, 3)
|
||||
params = generate_params(subkey1, batch_size, dim)
|
||||
old_params = generate_params(subkey2, batch_size, dim)
|
||||
proj_fn(params, old_params)
|
||||
end_time = time.time()
|
||||
|
||||
print(f"Wasserstein Projection:")
|
||||
print(f"Average time per projection: {(end_time - start_time) / n_iterations * 1000:.3f} ms")
|
||||
print(f"Total time for {n_iterations} iterations: {end_time - start_time:.3f} s")
|
||||
|
||||
if __name__ == "__main__":
|
||||
main()
|
||||
@@ -94,8 +94,8 @@ def test_diagonal_projection(ProjectionClass, needs_cpp, gaussian_params):
|
||||
assert jnp.all(jnp.isfinite(proj_params["scale"]))
|
||||
assert jnp.all(proj_params["scale"] > 0)
|
||||
|
||||
# Only check KL bounds for KL projection (and W2, which should approx hold as well)
|
||||
if ProjectionClass in [KLProjection, WassersteinProjection]:
|
||||
# Only check KL bounds for KL projection
|
||||
if ProjectionClass in [KLProjection]:
|
||||
kl = compute_gaussian_kl(proj_params, gaussian_params["old_params"])
|
||||
max_kl = (mean_bound + cov_bound) * 1.1 # Allow 10% margin
|
||||
|
||||
@@ -151,6 +151,10 @@ def test_full_covariance_projection(ProjectionClass):
|
||||
eigvals = jnp.linalg.eigvalsh(cov)
|
||||
assert jnp.all(eigvals > 0)
|
||||
|
||||
# Check trust region loss computation works
|
||||
tr_loss = proj.get_trust_region_loss(params, proj_params)
|
||||
assert jnp.isfinite(tr_loss)
|
||||
|
||||
# Only check KL bounds for KL projection
|
||||
if ProjectionClass in [KLProjection]:
|
||||
kl = compute_gaussian_kl(proj_params, old_params, full_cov=True)
|
||||
|
||||
Reference in New Issue
Block a user