pymc.backends.zarr.ZarrChain#
- class pymc.backends.zarr.ZarrChain(store, stats_bijection, synchronizer=None, model=None, vars=None, test_point=None, draws_per_chunk=1, fn=None)[source]#
Interface object to interact with a single chain in a
ZarrTrace
.- Parameters:
- store
zarr.storage.BaseStore
|collections.abc.MutableMapping
The store object where the zarr groups and arrays will be stored and read from. This store must exist before creating a
ZarrChain
object.ZarrChain
are only intended to be used as interfaces to the individual chains ofZarrTrace
objects. This means that theZarrTrace
should be the one that creates the store that is then provided to aZarrChain
.- stats_bijection
pymc.step_methods.compound.StatsBijection
An object that maps between a list of step method stats and a dictionary of said stats with the accompanying stepper index.
- synchronizer
zarr.sync.Synchronizer
|None
The synchronizer to use for the underlying zarr arrays.
- model
Model
If None, the model is taken from the with context.
- vars
Sequence
[TensorVariable
] |None
Sampling values will be stored for these variables. If None, model.unobserved_RVs is used.
- test_point
dict
[str
,numpy.ndarray
] |None
This is not used and is inherited from the signature of
BaseTrace
, which uses it to determine the shape and dtype of vars.- draws_per_chunk
int
The number of draws that make up a chunk in the variable’s posterior array. The interface only writes the samples to the store once a chunk is completely filled.
- store
Methods
ZarrChain.__init__
(store, stats_bijection[, ...])ZarrChain.buffer
(group, var_name, value)Close the backend.
Write the data stored in the internal buffer to the desired zarr store.
ZarrChain.get_sampler_stats
(stat_name[, ...])Get sampler statistics from the trace.
ZarrChain.get_values
(varname[, burn, thin])Get values from trace.
ZarrChain.link_stepper
(step_method)Provide a reference to the step method used during sampling.
ZarrChain.point
(idx)Return point values at idx for current chain.
ZarrChain.record
(draw, stats)Record the step method's returned draw and stats.
ZarrChain.record_sampling_state
([step])Record the sampling state information to the store's
_sampling_state
group.ZarrChain.setup
(draws, chain, sampler_vars)Perform chain-specific setup.
ZarrChain.store_sampling_state
(sampling_state)Attributes
stat_names
chain
Chain number.
varnames
Names of tracked variables.
sampler_vars
Sampler stats for each sampler.