mirror of
				https://github.com/Brandon-Rozek/matmod.git
				synced 2025-11-03 03:11:12 +00:00 
			
		
		
		
	Code cleanup
This commit is contained in:
		
							parent
							
								
									fa9e5026ca
								
							
						
					
					
						commit
						01204a9551
					
				
					 4 changed files with 286 additions and 353 deletions
				
			
		
							
								
								
									
										200
									
								
								vsp.py
									
										
									
									
									
								
							
							
						
						
									
										200
									
								
								vsp.py
									
										
									
									
									
								
							| 
						 | 
				
			
			@ -2,6 +2,7 @@
 | 
			
		|||
Check to see if the model has the variable
 | 
			
		||||
sharing property.
 | 
			
		||||
"""
 | 
			
		||||
from collections import defaultdict
 | 
			
		||||
from itertools import chain, combinations, product
 | 
			
		||||
from typing import List, Optional, Set, Tuple
 | 
			
		||||
from common import set_to_str
 | 
			
		||||
| 
						 | 
				
			
			@ -9,75 +10,36 @@ from model import (
 | 
			
		|||
    Model, model_closure, ModelFunction, ModelValue, OrderTable
 | 
			
		||||
)
 | 
			
		||||
 | 
			
		||||
def preseed(
 | 
			
		||||
        initial_set: Set[ModelValue],
 | 
			
		||||
        cache:List[Tuple[Set[ModelValue], Set[ModelValue]]]):
 | 
			
		||||
    """
 | 
			
		||||
    Given a cache of previous model_closure calls,
 | 
			
		||||
    use this to compute an initial model closure
 | 
			
		||||
    set based on the initial set.
 | 
			
		||||
class Cache:
 | 
			
		||||
    def __init__(self):
 | 
			
		||||
        # input size -> cached (inputs, outputs)
 | 
			
		||||
        self.c = defaultdict(list)
 | 
			
		||||
 | 
			
		||||
    Basic Idea:
 | 
			
		||||
    Let {1, 2, 3} -> X be in the cache.
 | 
			
		||||
    If {1,2,3} is a subset of initial set,
 | 
			
		||||
    then X is the subset of the output of model_closure.
 | 
			
		||||
    def add(self, i: Set[ModelValue], o: Set[ModelValue]):
 | 
			
		||||
        self.c[len(i)].append((i, o))
 | 
			
		||||
 | 
			
		||||
    This is used to speed up subsequent calls to model_closure
 | 
			
		||||
    """
 | 
			
		||||
    candidate_preseed: Tuple[Set[ModelValue], int] = (None, None)
 | 
			
		||||
    def get_closest(self, initial_set: Set[ModelValue]) -> Optional[Tuple[Set[ModelValue], bool]]:
 | 
			
		||||
        """
 | 
			
		||||
        Iterate through our cache starting with the cached
 | 
			
		||||
        inputs closest in size to the initial_set and
 | 
			
		||||
        find the one that's a subset of initial_set.
 | 
			
		||||
 | 
			
		||||
    for i, o in cache:
 | 
			
		||||
        if i < initial_set:
 | 
			
		||||
            cost = len(initial_set - i)
 | 
			
		||||
            # If i is a subset with less missing elements than
 | 
			
		||||
            # the previous candidate, then it's the new candidate.
 | 
			
		||||
            if candidate_preseed[1] is None or cost < candidate_preseed[1]:
 | 
			
		||||
                candidate_preseed = o, cost
 | 
			
		||||
        Returns cached_output, and whether the initial_set is the same
 | 
			
		||||
        as the cached_input.
 | 
			
		||||
        """
 | 
			
		||||
        initial_set_size = len(initial_set)
 | 
			
		||||
        sizes = range(initial_set_size, 0, -1)
 | 
			
		||||
 | 
			
		||||
    same_set = candidate_preseed[1] == 0
 | 
			
		||||
    return candidate_preseed[0], same_set
 | 
			
		||||
        for size in sizes:
 | 
			
		||||
            if size not in self.c:
 | 
			
		||||
                continue
 | 
			
		||||
 | 
			
		||||
            for cached_input, cached_output in self.c[size]:
 | 
			
		||||
                if cached_input <= initial_set:
 | 
			
		||||
                    return cached_output, size == initial_set_size
 | 
			
		||||
 | 
			
		||||
def find_top(algebra: Set[ModelValue], mconjunction: Optional[ModelFunction], mdisjunction: Optional[ModelFunction]) -> Optional[ModelValue]:
 | 
			
		||||
    """
 | 
			
		||||
    Find the top of the order lattice.
 | 
			
		||||
    T || a = T, T && a = a for all a in the carrier set
 | 
			
		||||
    """
 | 
			
		||||
    if mconjunction is None or mdisjunction is None:
 | 
			
		||||
        return None
 | 
			
		||||
 | 
			
		||||
    for x in algebra:
 | 
			
		||||
        is_top = True
 | 
			
		||||
        for y in algebra:
 | 
			
		||||
            if mdisjunction(x, y) != x or mconjunction(x, y) != y:
 | 
			
		||||
                is_top = False
 | 
			
		||||
                break
 | 
			
		||||
        if is_top:
 | 
			
		||||
            return x
 | 
			
		||||
 | 
			
		||||
    print("[Warning] Failed to find the top of the lattice")
 | 
			
		||||
    return None
 | 
			
		||||
 | 
			
		||||
def find_bottom(algebra: Set[ModelValue], mconjunction: Optional[ModelFunction], mdisjunction: Optional[ModelFunction]) -> Optional[ModelValue]:
 | 
			
		||||
    """
 | 
			
		||||
    Find the bottom of the order lattice
 | 
			
		||||
    F || a = a, F && a = F for all a in the carrier set
 | 
			
		||||
    """
 | 
			
		||||
    if mconjunction is None or mdisjunction is None:
 | 
			
		||||
        return None
 | 
			
		||||
 | 
			
		||||
    for x in algebra:
 | 
			
		||||
        is_bottom = True
 | 
			
		||||
        for y in algebra:
 | 
			
		||||
            if mdisjunction(x, y) != y or mconjunction(x, y) != x:
 | 
			
		||||
                is_bottom = False
 | 
			
		||||
                break
 | 
			
		||||
        if is_bottom:
 | 
			
		||||
            return x
 | 
			
		||||
 | 
			
		||||
    print("[Warning] Failed to find the bottom of the lattice")
 | 
			
		||||
    return None
 | 
			
		||||
 | 
			
		||||
def order_dependent(subalgebra1: Set[ModelValue], subalegbra2: Set[ModelValue], ordering: OrderTable):
 | 
			
		||||
    """
 | 
			
		||||
    Returns true if there exists a value in subalgebra1 that's less than a value in subalgebra2
 | 
			
		||||
| 
						 | 
				
			
			@ -106,17 +68,49 @@ Subalgebra 1: {set_to_str(self.subalgebra1)}
 | 
			
		|||
Subalgebra 2: {set_to_str(self.subalgebra2)}
 | 
			
		||||
"""
 | 
			
		||||
 | 
			
		||||
def quick_vsp_unsat_incomplete(xs, ys, model, top, bottom, negation_defined) -> bool:
 | 
			
		||||
    """
 | 
			
		||||
    Return True if VSP cannot be satisfied
 | 
			
		||||
    through some incomplete checks.
 | 
			
		||||
    """
 | 
			
		||||
    # If the left subalgebra contains bottom
 | 
			
		||||
    # or the right subalgebra contains top
 | 
			
		||||
    # skip this pair
 | 
			
		||||
    if top is not None and top in ys:
 | 
			
		||||
        return True
 | 
			
		||||
    if bottom is not None and bottom in xs:
 | 
			
		||||
        return True
 | 
			
		||||
 | 
			
		||||
    # If a subalgebra doesn't have at least one
 | 
			
		||||
    # designated value, move onto the next pair.
 | 
			
		||||
    # Depends on no intersection between xs and ys
 | 
			
		||||
    if xs.isdisjoint(model.designated_values):
 | 
			
		||||
        return True
 | 
			
		||||
 | 
			
		||||
    if ys.isdisjoint(model.designated_values):
 | 
			
		||||
        return True
 | 
			
		||||
 | 
			
		||||
    # If the two subalgebras intersect, move
 | 
			
		||||
    # onto the next pair.
 | 
			
		||||
    if not xs.isdisjoint(ys):
 | 
			
		||||
        return True
 | 
			
		||||
 | 
			
		||||
    # If the subalgebras are order-dependent, skip this pair
 | 
			
		||||
    if order_dependent(xs, ys, model.ordering):
 | 
			
		||||
        return True
 | 
			
		||||
    if negation_defined and order_dependent(ys, xs, model.ordering):
 | 
			
		||||
        return True
 | 
			
		||||
 | 
			
		||||
    # We can't immediately rule out that these
 | 
			
		||||
    # subalgebras don't exhibit VSP
 | 
			
		||||
    return False
 | 
			
		||||
 | 
			
		||||
def has_vsp(model: Model, impfunction: ModelFunction,
 | 
			
		||||
            mconjunction: Optional[ModelFunction] = None,
 | 
			
		||||
            mdisjunction: Optional[ModelFunction] = None,
 | 
			
		||||
            mnegation: Optional[ModelFunction] = None) -> VSP_Result:
 | 
			
		||||
            negation_defined: bool) -> VSP_Result:
 | 
			
		||||
    """
 | 
			
		||||
    Checks whether a model has the variable
 | 
			
		||||
    sharing property.
 | 
			
		||||
    """
 | 
			
		||||
    top = find_top(model.carrier_set, mconjunction, mdisjunction)
 | 
			
		||||
    bottom = find_bottom(model.carrier_set, mconjunction, mdisjunction)
 | 
			
		||||
 | 
			
		||||
    # NOTE: No models with only one designated
 | 
			
		||||
    # value satisfies VSP
 | 
			
		||||
    if len(model.designated_values) == 1:
 | 
			
		||||
| 
						 | 
				
			
			@ -124,68 +118,44 @@ def has_vsp(model: Model, impfunction: ModelFunction,
 | 
			
		|||
 | 
			
		||||
    assert model.ordering is not None, "Expected ordering table in model"
 | 
			
		||||
 | 
			
		||||
    top = model.ordering.top()
 | 
			
		||||
    bottom = model.ordering.bottom()
 | 
			
		||||
 | 
			
		||||
    # Compute I the set of tuples (x, y) where
 | 
			
		||||
    # x -> y does not take a designiated value
 | 
			
		||||
    I: Set[Tuple[ModelValue, ModelValue]] = set()
 | 
			
		||||
    I: List[Tuple[ModelValue, ModelValue]] = []
 | 
			
		||||
 | 
			
		||||
    for (x, y) in product(model.carrier_set, model.carrier_set):
 | 
			
		||||
        if impfunction(x, y) not in model.designated_values:
 | 
			
		||||
            I.add((x, y))
 | 
			
		||||
            I.append((x, y))
 | 
			
		||||
 | 
			
		||||
    # Construct the powerset of I without the empty set
 | 
			
		||||
    s = list(I)
 | 
			
		||||
    I_power = chain.from_iterable(combinations(s, r) for r in range(1, len(s) + 1))
 | 
			
		||||
    I_power = chain.from_iterable(combinations(I, r) for r in range(1, len(I) + 1))
 | 
			
		||||
    # ((x1, y1)), ((x1, y1), (x2, y2)), ...
 | 
			
		||||
 | 
			
		||||
    # Closure cache
 | 
			
		||||
    closure_cache: List[Tuple[Set[ModelValue], Set[ModelValue]]] = []
 | 
			
		||||
    closure_cache = Cache()
 | 
			
		||||
 | 
			
		||||
    # Find the subalgebras which falsify implication
 | 
			
		||||
    for xys in I_power:
 | 
			
		||||
 | 
			
		||||
        xs = {xy[0] for xy in xys}
 | 
			
		||||
        xs = { xy[0] for xy in xys }
 | 
			
		||||
        ys = { xy[1] for xy in xys }
 | 
			
		||||
 | 
			
		||||
        if quick_vsp_unsat_incomplete(xs, ys, model, top, bottom, negation_defined):
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        orig_xs = xs
 | 
			
		||||
        cached_xs = preseed(xs, closure_cache)
 | 
			
		||||
        if cached_xs[0] is not None:
 | 
			
		||||
        cached_xs = closure_cache.get_closest(xs)
 | 
			
		||||
        if cached_xs is not None:
 | 
			
		||||
            xs |= cached_xs[0]
 | 
			
		||||
 | 
			
		||||
        ys = {xy[1] for xy in xys}
 | 
			
		||||
        orig_ys = ys
 | 
			
		||||
        cached_ys = preseed(ys, closure_cache)
 | 
			
		||||
        if cached_ys[0] is not None:
 | 
			
		||||
        cached_ys = closure_cache.get_closest(ys)
 | 
			
		||||
        if cached_ys is not None:
 | 
			
		||||
            ys |= cached_ys[0]
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
        # NOTE: Optimziation before model_closure
 | 
			
		||||
        # If the two subalgebras intersect, move
 | 
			
		||||
        # onto the next pair.
 | 
			
		||||
        if len(xs & ys) > 0:
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        # NOTE: Optimization
 | 
			
		||||
        # If a subalgebra doesn't have at least one
 | 
			
		||||
        # designated value, move onto the next pair.
 | 
			
		||||
        # Depends on no intersection between xs and ys
 | 
			
		||||
        if len(xs & model.designated_values) == 0:
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        if len(ys & model.designated_values) == 0:
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        # NOTE: Optimization
 | 
			
		||||
        # If the left subalgebra contains bottom
 | 
			
		||||
        # or the right subalgebra contains top
 | 
			
		||||
        # skip this pair
 | 
			
		||||
        if top is not None and top in ys:
 | 
			
		||||
            continue
 | 
			
		||||
        if bottom is not None and bottom in xs:
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        # NOTE: Optimization
 | 
			
		||||
        # If the subalgebras are order-dependent, skip this pair
 | 
			
		||||
        if order_dependent(xs, ys, model.ordering):
 | 
			
		||||
            continue
 | 
			
		||||
        if mnegation is not None and order_dependent(ys, xs, model.ordering):
 | 
			
		||||
        xs_ys_updated = cached_xs is not None or cached_ys is not None
 | 
			
		||||
        if xs_ys_updated and quick_vsp_unsat_incomplete(xs, ys, model, top, bottom, negation_defined):
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        # Compute the closure of all operations
 | 
			
		||||
| 
						 | 
				
			
			@ -193,8 +163,8 @@ def has_vsp(model: Model, impfunction: ModelFunction,
 | 
			
		|||
        carrier_set_left: Set[ModelValue] = model_closure(xs, model.logical_operations, bottom)
 | 
			
		||||
 | 
			
		||||
        # Save to cache
 | 
			
		||||
        if cached_xs[0] is not None and not cached_ys[1]:
 | 
			
		||||
            closure_cache.append((orig_xs, carrier_set_left))
 | 
			
		||||
        if cached_xs is None or (cached_xs is not None and not cached_xs[1]):
 | 
			
		||||
            closure_cache.add(orig_xs, carrier_set_left)
 | 
			
		||||
 | 
			
		||||
        if bottom is not None and bottom in carrier_set_left:
 | 
			
		||||
            continue
 | 
			
		||||
| 
						 | 
				
			
			@ -204,15 +174,15 @@ def has_vsp(model: Model, impfunction: ModelFunction,
 | 
			
		|||
        carrier_set_right: Set[ModelValue] = model_closure(ys, model.logical_operations, top)
 | 
			
		||||
 | 
			
		||||
        # Save to cache
 | 
			
		||||
        if cached_ys[0] is not None and not cached_ys[1]:
 | 
			
		||||
            closure_cache.append((orig_ys, carrier_set_right))
 | 
			
		||||
        if cached_ys is None or (cached_ys is not None and not cached_ys[1]):
 | 
			
		||||
            closure_cache.add(orig_ys, carrier_set_right)
 | 
			
		||||
 | 
			
		||||
        if top is not None and top in carrier_set_right:
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        # If the carrier set intersects, then move on to the next
 | 
			
		||||
        # subalgebra
 | 
			
		||||
        if len(carrier_set_left & carrier_set_right) > 0:
 | 
			
		||||
        if not carrier_set_left.isdisjoint(carrier_set_right):
 | 
			
		||||
            continue
 | 
			
		||||
 | 
			
		||||
        # See if for all pairs in the subalgebras, that
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
	Add table
		Add a link
		
	
		Reference in a new issue