def ident_remove(expr):
""" Remove identities """
ids = map(isid, expr.args)
if sum(ids) == 0: # No identities. Common case
return expr
elif sum(ids) != len(ids): # there is at least one non-identity
return new(expr.__class__,
*[arg for arg, x in zip(expr.args, ids) if not x])
else:
return new(expr.__class__, expr.args[0])
def ident_remove(expr):
""" Remove identities """
ids = map(isid, expr.args)
if sum(ids) == 0: # No identities. Common case
return expr
elif sum(ids) != len(ids): # there is at least one non-identity
return new(expr.__class__,
*[arg for arg, x in zip(expr.args, ids) if not x])
else:
return new(expr.__class__, expr.args[0])
def conglomerate(expr):
""" Conglomerate together identical args x + x -> 2x """
groups = sift(expr.args, key)
counts = dict((k, sum(map(count, args))) for k, args in groups.items())
newargs = [combine(cnt, mat) for mat, cnt in counts.items()]
if set(newargs) != set(expr.args):
return new(type(expr), *newargs)
else:
return expr
def conglomerate(expr):
""" Conglomerate together identical args x + x -> 2x """
groups = sift(expr.args, key)
counts = dict((k, sum(map(count, args))) for k, args in groups.items())
newargs = [combine(cnt, mat) for mat, cnt in counts.items()]
if set(newargs) != set(expr.args):
return new(type(expr), *newargs)
else:
return expr
def flatten(expr, new=new):
""" Flatten T(a, b, T(c, d), T2(e)) to T(a, b, c, d, T2(e)) """
cls = expr.__class__
args = []
for arg in expr.args:
if arg.__class__ == cls:
args.extend(arg.args)
else:
args.append(arg)
return new(expr.__class__, *args)
def flatten(expr):
""" Flatten T(a, b, T(c, d), T2(e)) to T(a, b, c, d, T2(e)) """
cls = expr.__class__
args = []
for arg in expr.args:
if arg.__class__ == cls:
args.extend(arg.args)
else:
args.append(arg)
return new(expr.__class__, *args)
def __add__(self, item): return new(self, [*self, item])
def all_rl(expr):
if is_leaf(expr):
return expr
else:
args = map(rule, expr.args)
return new(type(expr), *args)
def top_down_rl(expr):
newexpr = rule(expr)
if newexpr.is_Atom:
return newexpr
return new(newexpr.__class__, *map(top_down_rl, newexpr.args))
def bottom_up_rl(expr):
if expr.is_Atom:
return rule(expr)
else:
return rule(new(expr.__class__, *map(bottom_up_rl, expr.args)))
def bottom_up_rl(expr):
if is_leaf(expr):
return rule(expr)
else:
return rule(new(type(expr), *map(bottom_up_rl, expr.args)))
def __mul__(self, other): return new(self, zip(self, other))
def __rmul__(self, other): return new(self, zip(other, self))
def __rand__(self, other): return new(self, [*other, *self])
def __and__(self, other): return new(self, [*self, *other])
def top_down_rl(expr):
newexpr = rule(expr)
if is_leaf(newexpr):
return newexpr
return new(type(newexpr), *map(top_down_rl, newexpr.args))
def bottom_up_rl(expr):
if is_leaf(expr):
return rule(expr)
else:
return rule(new(type(expr), *map(bottom_up_rl, expr.args)))
def top_down_rl(expr):
newexpr = rule(expr)
if is_leaf(newexpr):
return newexpr
return new(type(newexpr), *map(top_down_rl, newexpr.args))
def sort_rl(expr):
return new(expr.__class__, *sorted(expr.args, key=key))
def __radd__(self, item): return new(self, [item, *self])
def bottom_up_rl(expr):
if not isinstance(expr, Basic) or expr.is_Atom:
return rule(expr)
else:
return rule(new(expr.__class__, *map(bottom_up_rl, expr.args)))
def top_down_rl(expr):
newexpr = rule(expr)
if not isinstance(newexpr, Basic) or newexpr.is_Atom:
return newexpr
return new(newexpr.__class__, *map(top_down_rl, newexpr.args))
def sort_rl(expr):
return new(expr.__class__, *sorted(expr.args, key=key))
def all_rl(expr):
if is_leaf(expr):
return expr
else:
args = map(rule, expr.args)
return new(type(expr), *args)