[Bug] model_list_to_batched ignores the covar module of the input models #1411
Description
🐛 Bug
model_list_to_batched ignores the covariance module of the input model-list, and produces a batched model with the default covariance module. If the input model-list covar module does not have priors compatible with the default covar module, then it just errors out.
Originally reported in #1409.
To reproduce
** Code snippet to reproduce **
import gpytorch
import torch
from botorch.models.converter import model_list_to_batched
from botorch.models.gp_regression import SingleTaskGP
from botorch.models.model_list_gp_regression import ModelListGP
from gpytorch.kernels.rbf_kernel import RBFKernel
from gpytorch.kernels.scale_kernel import ScaleKernel
train_X = torch.rand(5, 2)
train_Y = torch.randn(5, 2)
model_list = ModelListGP(
*[
SingleTaskGP(
train_X=train_X,
train_Y=train_Y[:, i : i + 1],
covar_module=ScaleKernel(
base_kernel=RBFKernel( # Note the RBF kernel here.
ard_num_dims=2,
lengthscale_prior=gpytorch.priors.GammaPrior(3.0, 6.0),
),
outputscale_prior=gpytorch.priors.GammaPrior(2.0, 0.15),
),
)
for i in range(2)
]
)
batched_model = model_list_to_batched(model_list)
# Has Matern kernel with the default priors.
print(batched_model)** Stack trace/error message **
SingleTaskGP(
(likelihood): GaussianLikelihood(
(noise_covar): HomoskedasticNoise(
(noise_prior): GammaPrior()
(raw_noise_constraint): GreaterThan(1.000E-04)
)
)
(mean_module): ConstantMean()
(covar_module): ScaleKernel(
(base_kernel): MaternKernel(
(lengthscale_prior): GammaPrior()
(raw_lengthscale_constraint): Positive()
)
(outputscale_prior): GammaPrior()
(raw_outputscale_constraint): Positive()
)
)
If the priors are commented out:
'ScaleKernel' object has no attribute 'outputscale_prior'
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
/mnt/xarfuse/uid-352651/c1da8b8f-seed-nspid4026531836_cgpid13510401-ns-4026531840/gpytorch/module.py in __getattr__(self, name)
432 try:
--> 433 return super().__getattribute__(name)
434 except AttributeError:
AttributeError: 'ScaleKernel' object has no attribute 'outputscale_prior'
During handling of the above exception, another exception occurred:
AttributeError Traceback (most recent call last)
<ipython-input-130-a5251b88a562> in <module>
26 )
27
---> 28 batched_model = model_list_to_batched(model_list)
29 # Has Matern kernel with the default priors.
30 print(batched_model)
/mnt/xarfuse/uid-352651/c1da8b8f-seed-nspid4026531836_cgpid13510401-ns-4026531840/botorch/models/converter.py in model_list_to_batched(model_list)
163 # ensure scalars agree (TODO: Allow different priors for different outputs)
164 for n in non_adjusted_batch_keys:
--> 165 v0 = _get_module(models[0], n)
166 if not all(torch.equal(_get_module(m, n), v0) for m in models[1:]):
167 raise UnsupportedError("All scalars must have the same value.")
/mnt/xarfuse/uid-352651/c1da8b8f-seed-nspid4026531836_cgpid13510401-ns-4026531840/botorch/models/converter.py in _get_module(module, name)
45 if name != "":
46 for a in name.split("."):
---> 47 current = getattr(current, a)
48 return current
49
/mnt/xarfuse/uid-352651/c1da8b8f-seed-nspid4026531836_cgpid13510401-ns-4026531840/gpytorch/module.py in __getattr__(self, name)
433 return super().__getattribute__(name)
434 except AttributeError:
--> 435 raise e
436
437
/mnt/xarfuse/uid-352651/c1da8b8f-seed-nspid4026531836_cgpid13510401-ns-4026531840/gpytorch/module.py in __getattr__(self, name)
428 def __getattr__(self, name):
429 try:
--> 430 return super().__getattr__(name)
431 except AttributeError as e:
432 try:
/mnt/xarfuse/uid-352651/c1da8b8f-seed-nspid4026531836_cgpid13510401-ns-4026531840/torch/nn/modules/module.py in __getattr__(self, name)
1263 if name in modules:
1264 return modules[name]
-> 1265 raise AttributeError("'{}' object has no attribute '{}'".format(
1266 type(self).__name__, name))
1267
AttributeError: 'ScaleKernel' object has no attribute 'outputscale_prior'
Expected Behavior
The returned model should have the same type of covar module as the input model.
System information
BoTorch latest.