Source code for gensbi.recipes.simformer
"""
Pipeline for training and using a Simformer model for simulation-based inference.
"""
import jax
import jax.numpy as jnp
from flax import config, nnx
import yaml
from gensbi.models import (
Simformer,
SimformerParams,
)
from gensbi.recipes.joint_pipeline import JointFlowPipeline, JointDiffusionPipeline
[docs]
def parse_simformer_params(config_path: str):
"""
Parse a Simformer configuration file.
Parameters
----------
config_path : str
Path to the configuration file.
Returns
-------
config : dict
Parsed configuration dictionary.
"""
with open(config_path, "r") as f:
config = yaml.safe_load(f)
model_params = config.get("model", {})
params_dict = dict(
in_channels=model_params.get("in_channels", 1),
dim_value=model_params.get("dim_value", 40),
dim_id=model_params.get("dim_id", 40),
dim_condition=model_params.get("dim_condition", 10),
fourier_features=model_params.get("fourier_features", 128),
num_heads=model_params.get("num_heads", 4),
num_layers=model_params.get("num_layers", 8),
widening_factor=model_params.get("widening_factor", 3),
qkv_features=model_params.get("qkv_features", 90),
num_hidden_layers=model_params.get("num_hidden_layers", 1),
)
return params_dict
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def parse_training_config(config_path: str):
"""
Parse a training configuration file.
Parameters
----------
config_path : str
Path to the configuration file.
Returns
-------
config : dict
Parsed configuration dictionary.
"""
with open(config_path, "r") as f:
config = yaml.safe_load(f)
# Training parameters
train_params = config.get("training", {})
multistep = train_params.get("multistep", 1)
experiment_id = train_params.get("experiment_id", 1)
early_stopping = train_params.get("early_stopping", True)
nsteps = train_params.get("nsteps", 30000) * multistep
val_every = train_params.get("val_every", 100) * multistep
# Optimizer parameters
opt_params = config.get("optimizer", {})
MAX_LR = opt_params.get("max_lr", 1e-3)
MIN_LR = opt_params.get("min_lr", 0.0)
MIN_SCALE = MIN_LR / MAX_LR if MAX_LR > 0 else 0.0
ema_decay = opt_params.get("ema_decay", 0.999)
decay_transition = opt_params.get("decay_transition", 0.85)
warmup_steps = opt_params.get("warmup_steps", 500)
training_config = {}
# overwrite the defaults with the config file values
training_config["nsteps"] = nsteps
training_config["ema_decay"] = ema_decay
training_config["decay_transition"] = decay_transition
training_config["max_lr"] = MAX_LR
training_config["min_lr"] = MIN_LR
training_config["min_scale"] = MIN_SCALE
training_config["val_every"] = val_every
training_config["early_stopping"] = early_stopping
training_config["experiment_id"] = experiment_id
training_config["multistep"] = multistep
training_config["warmup_steps"] = warmup_steps
return training_config
[docs]
class SimformerFlowPipeline(JointFlowPipeline):
def __init__(
self,
train_dataset,
val_dataset,
dim_obs: int,
dim_cond: int,
ch_obs: int = 1,
params=None,
training_config=None,
edge_mask=None,
condition_mask_kind="structured",
):
"""
Flow pipeline for training and using a Simformer model for simulation-based inference.
Parameters
----------
train_dataset : grain dataset or iterator over batches
Training dataset.
val_dataset : grain dataset or iterator over batches
Validation dataset.
dim_obs : int
Dimension of the parameter space.
dim_cond : int
Dimension of the observation space.
ch_obs : int
Number of channels in the observation data.
params : SimformerParams, optional
Parameters for the Simformer model. If None, default parameters are used.
training_config : dict, optional
Configuration for training. If None, default configuration is used.
edge_mask : jnp.ndarray, optional
Edge mask for the Simformer model. If None, no mask is applied.
condition_mask_kind : str, optional
Kind of condition mask to use. One of ["structured", "posterior"].
Examples
--------
Minimal example on how to instantiate and use the SimformerFlowPipeline:
.. literalinclude:: /examples/simformer_flow_pipeline.py
:language: python
:linenos:
.. image:: /examples/simformer_flow_pipeline_marginals.png
:width: 600
.. note::
If you plan on using multiprocessing prefetching, ensure that your script is wrapped
in a ``if __name__ == "__main__":`` guard.
See https://docs.python.org/3/library/multiprocessing.html
"""
if params is None:
params = self._get_default_params()
model = self._make_model(params)
super().__init__(
model=model,
train_dataset=train_dataset,
val_dataset=val_dataset,
dim_obs=dim_obs,
dim_cond=dim_cond,
ch_obs=ch_obs,
params=params,
training_config=training_config,
condition_mask_kind=condition_mask_kind,
)
@classmethod
[docs]
def init_pipeline_from_config(
cls,
train_dataset,
val_dataset,
dim_obs: int,
dim_cond: int,
config_path: str,
checkpoint_dir: str,
):
"""
Initialize the pipeline from a configuration file.
Parameters
----------
config_path : str
Path to the configuration file.
"""
with open(config_path, "r") as f:
config = yaml.safe_load(f)
# methodology
strategy = config.get("strategy", {})
method = strategy.get("method")
model_type = strategy.get("model")
assert (
method == "flow"
), f"Method {method} not supported in SimformerFlowPipeline."
assert (
model_type == "simformer"
), f"Model type {model_type} not supported in SimformerFlowPipeline."
# Model parameters from config
dim_joint = dim_obs + dim_cond
params_dict = parse_simformer_params(config_path)
params = SimformerParams(
rngs=nnx.Rngs(0),
dim_joint=dim_joint,
**params_dict,
)
# Training parameters
training_config = cls.get_default_training_config()
training_config["checkpoint_dir"] = checkpoint_dir
training_config_ = parse_training_config(config_path)
for key, value in training_config_.items():
training_config[key] = value # update with config file values
pipeline = cls(
train_dataset,
val_dataset,
dim_obs,
dim_cond,
ch_obs=params.in_channels,
params=params,
training_config=training_config,
)
return pipeline
[docs]
def _make_model(self, params):
"""
Create and return the Simformer model to be trained.
"""
model = Simformer(params)
return model
[docs]
def _get_default_params(self):
"""
Return default parameters for the Simformer model.
"""
params = SimformerParams(
rngs=nnx.Rngs(0),
in_channels=self.ch_obs,
dim_value=40,
dim_id=40,
dim_condition=10,
dim_joint=self.dim_joint,
fourier_features=128,
num_heads=4,
num_layers=8,
widening_factor=3,
qkv_features=40,
num_hidden_layers=1,
)
return params
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def sample(
self, key, x_o, nsamples=10_000, step_size=0.01, use_ema=True, time_grid=None
):
model_extras = {
"edge_mask": self.edge_mask,
}
return super().sample(
key,
x_o,
nsamples=nsamples,
step_size=step_size,
use_ema=use_ema,
time_grid=time_grid,
**model_extras,
)
# def compute_unnorm_logprob(
# self, x_1, x_o, step_size=0.01, use_ema=True, time_grid=None
# ):
# model_extras = {
# "edge_mask": self.edge_mask,
# }
# return super().compute_unnorm_logprob(
# x_1,
# x_o,
# step_size=step_size,
# use_ema=use_ema,
# time_grid=time_grid,
# **model_extras,
# )
[docs]
class SimformerDiffusionPipeline(JointDiffusionPipeline):
def __init__(
self,
train_dataset,
val_dataset,
dim_obs: int,
dim_cond: int,
ch_obs: int = 1,
params=None,
training_config=None,
edge_mask=None,
condition_mask_kind="structured",
):
"""
Diffusion pipeline for training and using a Simformer model for simulation-based inference.
Parameters
----------
train_dataset : grain dataset or iterator over batches
Training dataset.
val_dataset : grain dataset or iterator over batches
Validation dataset.
dim_obs : int
Dimension of the parameter space.
dim_cond : int
Dimension of the observation space.
params : SimformerParams, optional
Parameters for the Simformer model. If None, default parameters are used.
training_config : dict, optional
Configuration for training. If None, default configuration is used.
edge_mask : jnp.ndarray, optional
Edge mask for the Simformer model. If None, no mask is applied.
condition_mask_kind : str, optional
Kind of condition mask to use. One of ["structured", "posterior"].
Examples
--------
Minimal example on how to instantiate and use the SimformerDiffusionPipeline:
.. literalinclude:: /examples/simformer_diffusion_pipeline.py
:language: python
:linenos:
.. image:: /examples/simformer_diffusion_pipeline_marginals.png
:width: 600
.. note::
If you plan on using multiprocessing prefetching, ensure that your script is wrapped
in a ``if __name__ == "__main__":`` guard.
See https://docs.python.org/3/library/multiprocessing.html
"""
if params is None:
params = self._get_default_params()
model = self._make_model(params)
super().__init__(
model=model,
train_dataset=train_dataset,
val_dataset=val_dataset,
dim_obs=dim_obs,
dim_cond=dim_cond,
ch_obs=ch_obs,
params=params,
training_config=training_config,
condition_mask_kind=condition_mask_kind,
)
@classmethod
[docs]
def init_pipeline_from_config(
cls,
train_dataset,
val_dataset,
dim_obs: int,
dim_cond: int,
config_path: str,
checkpoint_dir: str,
):
"""
Initialize the pipeline from a configuration file.
Parameters
----------
config_path : str
Path to the configuration file.
"""
with open(config_path, "r") as f:
config = yaml.safe_load(f)
# methodology
strategy = config.get("strategy", {})
method = strategy.get("method")
model_type = strategy.get("model")
assert (
method == "diffusion"
), f"Method {method} not supported in SimformerDiffusionPipeline."
assert (
model_type == "simformer"
), f"Model type {model_type} not supported in SimformerDiffusionPipeline."
# Model parameters from config
dim_joint = dim_obs + dim_cond
params_dict = parse_simformer_params(config_path)
params = SimformerParams(
rngs=nnx.Rngs(0),
dim_joint=dim_joint,
**params_dict,
)
# Training parameters
training_config = cls.get_default_training_config()
training_config["checkpoint_dir"] = checkpoint_dir
training_config_ = parse_training_config(config_path)
for key, value in training_config_.items():
training_config[key] = value # update with config file values
pipeline = cls(
train_dataset,
val_dataset,
dim_obs,
dim_cond,
ch_obs=params.in_channels,
params=params,
training_config=training_config,
)
return pipeline
[docs]
def _make_model(self, params):
"""
Create and return the Simformer model to be trained.
"""
model = Simformer(params)
return model
[docs]
def _get_default_params(self):
"""
Return default parameters for the Simformer model.
"""
params = SimformerParams(
in_channels=self.ch_obs,
dim_value=40,
dim_id=40,
dim_condition=10,
dim_joint=self.dim_joint,
fourier_features=128,
num_heads=4,
num_layers=8,
widening_factor=3,
qkv_features=40,
rngs=nnx.Rngs(0),
num_hidden_layers=1,
)
return params
[docs]
def sample(
self,
key,
x_o,
nsamples=10_000,
nsteps=18,
use_ema=True,
return_intermediates=False,
):
model_extras = {
"edge_mask": self.edge_mask,
}
return super().sample(
key,
x_o,
nsamples=nsamples,
nsteps=nsteps,
use_ema=use_ema,
return_intermediates=return_intermediates,
**model_extras,
)