Source code for pymc.step_methods.compound

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"""
Created on Mar 7, 2011

@author: johnsalvatier
"""


from typing import Tuple

from pymc.blocking import PointType, StatsType


[docs]class CompoundStep:
    """Step method composed of a list of several other step
    methods applied in sequence."""

[docs]    def __init__(self, methods):
        self.methods = list(methods)
        self.stats_dtypes = []
        for method in self.methods:
            self.stats_dtypes.extend(method.stats_dtypes)
        self.name = (
            f"Compound[{', '.join(getattr(m, 'name', 'UNNAMED_STEP') for m in self.methods)}]"
        )

[docs]    def step(self, point) -> Tuple[PointType, StatsType]:
        stats = []
        for method in self.methods:
            point, sts = method.step(point)
            stats.extend(sts)
        # Model logp can only be the logp of the _last_ stats,
        # if there is one. Pop all others.
        for sts in stats[:-1]:
            sts.pop("model_logp", None)
        return point, stats

[docs]    def stop_tuning(self):
        for method in self.methods:
            method.stop_tuning()

[docs]    def reset_tuning(self):
        for method in self.methods:
            if hasattr(method, "reset_tuning"):
                method.reset_tuning()

    @property
    def vars(self):
        return [var for method in self.methods for var in method.vars]