Source code for gpytorch.lazy.chol_lazy_tensor

#!/usr/bin/env python3

import torch

from .. import settings
from .batch_repeat_lazy_tensor import BatchRepeatLazyTensor
from .lazy_tensor import delazify
from .root_lazy_tensor import RootLazyTensor

[docs]class CholLazyTensor(RootLazyTensor): def __init__(self, chol): # Check that we have a lower triangular matrix if settings.debug.on(): delazy_chol = ( delazify(chol) if not isinstance(chol, BatchRepeatLazyTensor) else delazify(chol.base_lazy_tensor) ) mask = torch.ones(delazy_chol.shape[-2:], dtype=delazy_chol.dtype, device=delazy_chol.device).triu_(1) if torch.max(delazy_chol.mul(mask)).item() > 1e-3 and torch.equal(delazy_chol, delazy_chol): raise RuntimeError("CholLazyVariable should take a lower-triangular matrix in the constructor.") # Run super constructor super(CholLazyTensor, self).__init__(chol) @property def _chol(self): if not hasattr(self, "_chol_memo"): self._chol_memo = self.root.evaluate() return self._chol_memo @property def _chol_diag(self): if not hasattr(self, "_chol_diag_memo"): self._chol_diag_memo = self._chol.diagonal(dim1=-2, dim2=-1).clone() return self._chol_diag_memo def _cholesky(self): return self.root def _solve(self, rhs, preconditioner, num_tridiag=0): if num_tridiag: return super()._solve(rhs, preconditioner, num_tridiag=num_tridiag) else: return self.root._cholesky_solve(rhs) def inv_matmul(self, right_tensor, left_tensor=None): with settings.fast_computations(solves=False): return super().inv_matmul(right_tensor, left_tensor=left_tensor) def inv_quad_logdet(self, inv_quad_rhs=None, logdet=False, reduce_inv_quad=True): if not self.is_square: raise RuntimeError( "inv_quad_logdet only operates on (batches of) square (positive semi-definite) LazyTensors. " "Got a {} of size {}.".format(self.__class__.__name__, self.size()) ) if inv_quad_rhs is not None: if self.dim() == 2 and inv_quad_rhs.dim() == 1: if self.shape[-1] != inv_quad_rhs.numel(): raise RuntimeError( "LazyTensor (size={}) cannot be multiplied with right-hand-side Tensor (size={}).".format( self.shape, inv_quad_rhs.shape ) ) elif self.dim() != inv_quad_rhs.dim(): raise RuntimeError( "LazyTensor (size={}) and right-hand-side Tensor (size={}) should have the same number " "of dimensions.".format(self.shape, inv_quad_rhs.shape) ) elif self.shape[-1] != inv_quad_rhs.shape[-2]: raise RuntimeError( "LazyTensor (size={}) cannot be multiplied with right-hand-side Tensor (size={}).".format( self.shape, inv_quad_rhs.shape ) ) inv_quad_term = None logdet_term = None if inv_quad_rhs is not None: inv_quad_term = self.inv_quad(inv_quad_rhs, reduce_inv_quad=reduce_inv_quad) if logdet: logdet_term = self._chol_diag.pow(2).log().sum(-1) return inv_quad_term, logdet_term