Source code for sympy.polys.polyclasses

"""OO layer for several polynomial representations. """

from __future__ import print_function, division

from sympy import oo
from sympy.core.sympify import CantSympify
from sympy.polys.polyerrors import CoercionFailed, NotReversible, NotInvertible
from sympy.polys.polyutils import PicklableWithSlots


class GenericPoly(PicklableWithSlots):
    """Base class for low-level polynomial representations. """

    def ground_to_ring(f):
        """Make the ground domain a ring. """
        return f.set_domain(f.dom.get_ring())

    def ground_to_field(f):
        """Make the ground domain a field. """
        return f.set_domain(f.dom.get_field())

    def ground_to_exact(f):
        """Make the ground domain exact. """
        return f.set_domain(f.dom.get_exact())

    @classmethod
    def _perify_factors(per, result, include):
        if include:
            coeff, factors = result
        else:
            coeff = result

        factors = [ (per(g), k) for g, k in factors ]

        if include:
            return coeff, factors
        else:
            return factors

from sympy.polys.densebasic import (
    dmp_validate,
    dup_normal, dmp_normal,
    dup_convert, dmp_convert,
    dmp_from_sympy,
    dup_strip,
    dup_degree, dmp_degree_in,
    dmp_degree_list,
    dmp_negative_p,
    dup_LC, dmp_ground_LC,
    dup_TC, dmp_ground_TC,
    dmp_ground_nth,
    dmp_one, dmp_ground,
    dmp_zero_p, dmp_one_p, dmp_ground_p,
    dup_from_dict, dmp_from_dict,
    dmp_to_dict,
    dmp_deflate,
    dmp_inject, dmp_eject,
    dmp_terms_gcd,
    dmp_list_terms, dmp_exclude,
    dmp_slice_in, dmp_permute,
    dmp_to_tuple,)

from sympy.polys.densearith import (
    dmp_add_ground,
    dmp_sub_ground,
    dmp_mul_ground,
    dmp_quo_ground,
    dmp_exquo_ground,
    dmp_abs,
    dup_neg, dmp_neg,
    dup_add, dmp_add,
    dup_sub, dmp_sub,
    dup_mul, dmp_mul,
    dmp_sqr,
    dup_pow, dmp_pow,
    dmp_pdiv,
    dmp_prem,
    dmp_pquo,
    dmp_pexquo,
    dmp_div,
    dup_rem, dmp_rem,
    dmp_quo,
    dmp_exquo,
    dmp_add_mul, dmp_sub_mul,
    dmp_max_norm,
    dmp_l1_norm)

from sympy.polys.densetools import (
    dmp_clear_denoms,
    dmp_integrate_in,
    dmp_diff_in,
    dmp_eval_in,
    dup_revert,
    dmp_ground_trunc,
    dmp_ground_content,
    dmp_ground_primitive,
    dmp_ground_monic,
    dmp_compose,
    dup_decompose,
    dup_shift,
    dup_transform,
    dmp_lift)

from sympy.polys.euclidtools import (
    dup_half_gcdex, dup_gcdex, dup_invert,
    dmp_subresultants,
    dmp_resultant,
    dmp_discriminant,
    dmp_inner_gcd,
    dmp_gcd,
    dmp_lcm,
    dmp_cancel)

from sympy.polys.sqfreetools import (
    dup_gff_list,
    dmp_norm,
    dmp_sqf_p,
    dmp_sqf_norm,
    dmp_sqf_part,
    dmp_sqf_list, dmp_sqf_list_include)

from sympy.polys.factortools import (
    dup_cyclotomic_p, dmp_irreducible_p,
    dmp_factor_list, dmp_factor_list_include)

from sympy.polys.rootisolation import (
    dup_isolate_real_roots_sqf,
    dup_isolate_real_roots,
    dup_isolate_all_roots_sqf,
    dup_isolate_all_roots,
    dup_refine_real_root,
    dup_count_real_roots,
    dup_count_complex_roots,
    dup_sturm)

from sympy.polys.polyerrors import (
    UnificationFailed,
    PolynomialError)


def init_normal_DMP(rep, lev, dom):
    return DMP(dmp_normal(rep, lev, dom), dom, lev)


[docs]class DMP(PicklableWithSlots, CantSympify): """Dense Multivariate Polynomials over `K`. """ __slots__ = ['rep', 'lev', 'dom', 'ring'] def __init__(self, rep, dom, lev=None, ring=None): if lev is not None: if type(rep) is dict: rep = dmp_from_dict(rep, lev, dom) elif type(rep) is not list: rep = dmp_ground(dom.convert(rep), lev) else: rep, lev = dmp_validate(rep) self.rep = rep self.lev = lev self.dom = dom self.ring = ring def __repr__(f): return "%s(%s, %s, %s)" % (f.__class__.__name__, f.rep, f.dom, f.ring) def __hash__(f): return hash((f.__class__.__name__, f.to_tuple(), f.lev, f.dom, f.ring))
[docs] def unify(f, g): """Unify representations of two multivariate polynomials. """ if not isinstance(g, DMP) or f.lev != g.lev: raise UnificationFailed("can't unify %s with %s" % (f, g)) if f.dom == g.dom and f.ring == g.ring: return f.lev, f.dom, f.per, f.rep, g.rep else: lev, dom = f.lev, f.dom.unify(g.dom) ring = f.ring if g.ring is not None: if ring is not None: ring = ring.unify(g.ring) else: ring = g.ring F = dmp_convert(f.rep, lev, f.dom, dom) G = dmp_convert(g.rep, lev, g.dom, dom) def per(rep, dom=dom, lev=lev, kill=False): if kill: if not lev: return rep else: lev -= 1 return DMP(rep, dom, lev, ring) return lev, dom, per, F, G
[docs] def per(f, rep, dom=None, kill=False, ring=None): """Create a DMP out of the given representation. """ lev = f.lev if kill: if not lev: return rep else: lev -= 1 if dom is None: dom = f.dom if ring is None: ring = f.ring return DMP(rep, dom, lev, ring)
@classmethod def zero(cls, lev, dom, ring=None): return DMP(0, dom, lev, ring) @classmethod def one(cls, lev, dom, ring=None): return DMP(1, dom, lev, ring)
[docs] @classmethod def from_list(cls, rep, lev, dom): """Create an instance of ``cls`` given a list of native coefficients. """ return cls(dmp_convert(rep, lev, None, dom), dom, lev)
[docs] @classmethod def from_sympy_list(cls, rep, lev, dom): """Create an instance of ``cls`` given a list of SymPy coefficients. """ return cls(dmp_from_sympy(rep, lev, dom), dom, lev)
[docs] def to_dict(f, zero=False): """Convert ``f`` to a dict representation with native coefficients. """ return dmp_to_dict(f.rep, f.lev, f.dom, zero=zero)
[docs] def to_sympy_dict(f, zero=False): """Convert ``f`` to a dict representation with SymPy coefficients. """ rep = dmp_to_dict(f.rep, f.lev, f.dom, zero=zero) for k, v in rep.items(): rep[k] = f.dom.to_sympy(v) return rep
[docs] def to_list(f): """Convert ``f`` to a list representation with native coefficients. """ return f.rep
[docs] def to_sympy_list(f): """Convert ``f`` to a list representation with SymPy coefficients. """ def sympify_nested_list(rep): out = [] for val in rep: if isinstance(val, list): out.append(sympify_nested_list(val)) else: out.append(f.dom.to_sympy(val)) return out return sympify_nested_list(f.rep)
[docs] def to_tuple(f): """ Convert ``f`` to a tuple representation with native coefficients. This is needed for hashing. """ return dmp_to_tuple(f.rep, f.lev)
[docs] @classmethod def from_dict(cls, rep, lev, dom): """Construct and instance of ``cls`` from a ``dict`` representation. """ return cls(dmp_from_dict(rep, lev, dom), dom, lev)
@classmethod def from_monoms_coeffs(cls, monoms, coeffs, lev, dom, ring=None): return DMP(dict(list(zip(monoms, coeffs))), dom, lev, ring)
[docs] def to_ring(f): """Make the ground domain a ring. """ return f.convert(f.dom.get_ring())
[docs] def to_field(f): """Make the ground domain a field. """ return f.convert(f.dom.get_field())
[docs] def to_exact(f): """Make the ground domain exact. """ return f.convert(f.dom.get_exact())
[docs] def convert(f, dom): """Convert the ground domain of ``f``. """ if f.dom == dom: return f else: return DMP(dmp_convert(f.rep, f.lev, f.dom, dom), dom, f.lev)
[docs] def slice(f, m, n, j=0): """Take a continuous subsequence of terms of ``f``. """ return f.per(dmp_slice_in(f.rep, m, n, j, f.lev, f.dom))
[docs] def coeffs(f, order=None): """Returns all non-zero coefficients from ``f`` in lex order. """ return [ c for _, c in dmp_list_terms(f.rep, f.lev, f.dom, order=order) ]
[docs] def monoms(f, order=None): """Returns all non-zero monomials from ``f`` in lex order. """ return [ m for m, _ in dmp_list_terms(f.rep, f.lev, f.dom, order=order) ]
[docs] def terms(f, order=None): """Returns all non-zero terms from ``f`` in lex order. """ return dmp_list_terms(f.rep, f.lev, f.dom, order=order)
[docs] def all_coeffs(f): """Returns all coefficients from ``f``. """ if not f.lev: if not f: return [f.dom.zero] else: return [ c for c in f.rep ] else: raise PolynomialError('multivariate polynomials not supported')
[docs] def all_monoms(f): """Returns all monomials from ``f``. """ if not f.lev: n = dup_degree(f.rep) if n < 0: return [(0,)] else: return [ (n - i,) for i, c in enumerate(f.rep) ] else: raise PolynomialError('multivariate polynomials not supported')
[docs] def all_terms(f): """Returns all terms from a ``f``. """ if not f.lev: n = dup_degree(f.rep) if n < 0: return [((0,), f.dom.zero)] else: return [ ((n - i,), c) for i, c in enumerate(f.rep) ] else: raise PolynomialError('multivariate polynomials not supported')
[docs] def lift(f): """Convert algebraic coefficients to rationals. """ return f.per(dmp_lift(f.rep, f.lev, f.dom), dom=f.dom.dom)
[docs] def deflate(f): """Reduce degree of `f` by mapping `x_i^m` to `y_i`. """ J, F = dmp_deflate(f.rep, f.lev, f.dom) return J, f.per(F)
[docs] def inject(f, front=False): """Inject ground domain generators into ``f``. """ F, lev = dmp_inject(f.rep, f.lev, f.dom, front=front) return f.__class__(F, f.dom.dom, lev)
[docs] def eject(f, dom, front=False): """Eject selected generators into the ground domain. """ F = dmp_eject(f.rep, f.lev, dom, front=front) return f.__class__(F, dom, f.lev - len(dom.symbols))
[docs] def exclude(f): r""" Remove useless generators from ``f``. Returns the removed generators and the new excluded ``f``. Examples ======== >>> from sympy.polys.polyclasses import DMP >>> from sympy.polys.domains import ZZ >>> DMP([[[ZZ(1)]], [[ZZ(1)], [ZZ(2)]]], ZZ).exclude() ([2], DMP([[1], [1, 2]], ZZ, None)) """ J, F, u = dmp_exclude(f.rep, f.lev, f.dom) return J, f.__class__(F, f.dom, u)
[docs] def permute(f, P): r""" Returns a polynomial in `K[x_{P(1)}, ..., x_{P(n)}]`. Examples ======== >>> from sympy.polys.polyclasses import DMP >>> from sympy.polys.domains import ZZ >>> DMP([[[ZZ(2)], [ZZ(1), ZZ(0)]], [[]]], ZZ).permute([1, 0, 2]) DMP([[[2], []], [[1, 0], []]], ZZ, None) >>> DMP([[[ZZ(2)], [ZZ(1), ZZ(0)]], [[]]], ZZ).permute([1, 2, 0]) DMP([[[1], []], [[2, 0], []]], ZZ, None) """ return f.per(dmp_permute(f.rep, P, f.lev, f.dom))
[docs] def terms_gcd(f): """Remove GCD of terms from the polynomial ``f``. """ J, F = dmp_terms_gcd(f.rep, f.lev, f.dom) return J, f.per(F)
[docs] def add_ground(f, c): """Add an element of the ground domain to ``f``. """ return f.per(dmp_add_ground(f.rep, f.dom.convert(c), f.lev, f.dom))
[docs] def sub_ground(f, c): """Subtract an element of the ground domain from ``f``. """ return f.per(dmp_sub_ground(f.rep, f.dom.convert(c), f.lev, f.dom))
[docs] def mul_ground(f, c): """Multiply ``f`` by a an element of the ground domain. """ return f.per(dmp_mul_ground(f.rep, f.dom.convert(c), f.lev, f.dom))
[docs] def quo_ground(f, c): """Quotient of ``f`` by a an element of the ground domain. """ return f.per(dmp_quo_ground(f.rep, f.dom.convert(c), f.lev, f.dom))
[docs] def exquo_ground(f, c): """Exact quotient of ``f`` by a an element of the ground domain. """ return f.per(dmp_exquo_ground(f.rep, f.dom.convert(c), f.lev, f.dom))
[docs] def abs(f): """Make all coefficients in ``f`` positive. """ return f.per(dmp_abs(f.rep, f.lev, f.dom))
[docs] def neg(f): """Negate all coefficients in ``f``. """ return f.per(dmp_neg(f.rep, f.lev, f.dom))
[docs] def add(f, g): """Add two multivariate polynomials ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_add(F, G, lev, dom))
[docs] def sub(f, g): """Subtract two multivariate polynomials ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_sub(F, G, lev, dom))
[docs] def mul(f, g): """Multiply two multivariate polynomials ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_mul(F, G, lev, dom))
[docs] def sqr(f): """Square a multivariate polynomial ``f``. """ return f.per(dmp_sqr(f.rep, f.lev, f.dom))
[docs] def pow(f, n): """Raise ``f`` to a non-negative power ``n``. """ if isinstance(n, int): return f.per(dmp_pow(f.rep, n, f.lev, f.dom)) else: raise TypeError("``int`` expected, got %s" % type(n))
[docs] def pdiv(f, g): """Polynomial pseudo-division of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) q, r = dmp_pdiv(F, G, lev, dom) return per(q), per(r)
[docs] def prem(f, g): """Polynomial pseudo-remainder of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_prem(F, G, lev, dom))
[docs] def pquo(f, g): """Polynomial pseudo-quotient of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_pquo(F, G, lev, dom))
[docs] def pexquo(f, g): """Polynomial exact pseudo-quotient of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_pexquo(F, G, lev, dom))
[docs] def div(f, g): """Polynomial division with remainder of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) q, r = dmp_div(F, G, lev, dom) return per(q), per(r)
[docs] def rem(f, g): """Computes polynomial remainder of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_rem(F, G, lev, dom))
[docs] def quo(f, g): """Computes polynomial quotient of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_quo(F, G, lev, dom))
[docs] def exquo(f, g): """Computes polynomial exact quotient of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) res = per(dmp_exquo(F, G, lev, dom)) if f.ring and res not in f.ring: from sympy.polys.polyerrors import ExactQuotientFailed raise ExactQuotientFailed(f, g, f.ring) return res
[docs] def degree(f, j=0): """Returns the leading degree of ``f`` in ``x_j``. """ if isinstance(j, int): return dmp_degree_in(f.rep, j, f.lev) else: raise TypeError("``int`` expected, got %s" % type(j))
[docs] def degree_list(f): """Returns a list of degrees of ``f``. """ return dmp_degree_list(f.rep, f.lev)
[docs] def total_degree(f): """Returns the total degree of ``f``. """ return max(sum(m) for m in f.monoms())
[docs] def homogenize(f, s): """Return homogeneous polynomial of ``f``""" td = f.total_degree() result = {} new_symbol = (s == len(f.terms()[0][0])) for term in f.terms(): d = sum(term[0]) if d < td: i = td - d else: i = 0 if new_symbol: result[term[0] + (i,)] = term[1] else: l = list(term[0]) l[s] += i result[tuple(l)] = term[1] return DMP(result, f.dom, f.lev + int(new_symbol), f.ring)
[docs] def homogeneous_order(f): """Returns the homogeneous order of ``f``. """ if f.is_zero: return -oo monoms = f.monoms() tdeg = sum(monoms[0]) for monom in monoms: _tdeg = sum(monom) if _tdeg != tdeg: return None return tdeg
[docs] def LC(f): """Returns the leading coefficient of ``f``. """ return dmp_ground_LC(f.rep, f.lev, f.dom)
[docs] def TC(f): """Returns the trailing coefficient of ``f``. """ return dmp_ground_TC(f.rep, f.lev, f.dom)
[docs] def nth(f, *N): """Returns the ``n``-th coefficient of ``f``. """ if all(isinstance(n, int) for n in N): return dmp_ground_nth(f.rep, N, f.lev, f.dom) else: raise TypeError("a sequence of integers expected")
[docs] def max_norm(f): """Returns maximum norm of ``f``. """ return dmp_max_norm(f.rep, f.lev, f.dom)
[docs] def l1_norm(f): """Returns l1 norm of ``f``. """ return dmp_l1_norm(f.rep, f.lev, f.dom)
[docs] def clear_denoms(f): """Clear denominators, but keep the ground domain. """ coeff, F = dmp_clear_denoms(f.rep, f.lev, f.dom) return coeff, f.per(F)
[docs] def integrate(f, m=1, j=0): """Computes the ``m``-th order indefinite integral of ``f`` in ``x_j``. """ if not isinstance(m, int): raise TypeError("``int`` expected, got %s" % type(m)) if not isinstance(j, int): raise TypeError("``int`` expected, got %s" % type(j)) return f.per(dmp_integrate_in(f.rep, m, j, f.lev, f.dom))
[docs] def diff(f, m=1, j=0): """Computes the ``m``-th order derivative of ``f`` in ``x_j``. """ if not isinstance(m, int): raise TypeError("``int`` expected, got %s" % type(m)) if not isinstance(j, int): raise TypeError("``int`` expected, got %s" % type(j)) return f.per(dmp_diff_in(f.rep, m, j, f.lev, f.dom))
[docs] def eval(f, a, j=0): """Evaluates ``f`` at the given point ``a`` in ``x_j``. """ if not isinstance(j, int): raise TypeError("``int`` expected, got %s" % type(j)) return f.per(dmp_eval_in(f.rep, f.dom.convert(a), j, f.lev, f.dom), kill=True)
[docs] def half_gcdex(f, g): """Half extended Euclidean algorithm, if univariate. """ lev, dom, per, F, G = f.unify(g) if not lev: s, h = dup_half_gcdex(F, G, dom) return per(s), per(h) else: raise ValueError('univariate polynomial expected')
[docs] def gcdex(f, g): """Extended Euclidean algorithm, if univariate. """ lev, dom, per, F, G = f.unify(g) if not lev: s, t, h = dup_gcdex(F, G, dom) return per(s), per(t), per(h) else: raise ValueError('univariate polynomial expected')
[docs] def invert(f, g): """Invert ``f`` modulo ``g``, if possible. """ lev, dom, per, F, G = f.unify(g) if not lev: return per(dup_invert(F, G, dom)) else: raise ValueError('univariate polynomial expected')
[docs] def revert(f, n): """Compute ``f**(-1)`` mod ``x**n``. """ if not f.lev: return f.per(dup_revert(f.rep, n, f.dom)) else: raise ValueError('univariate polynomial expected')
[docs] def subresultants(f, g): """Computes subresultant PRS sequence of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) R = dmp_subresultants(F, G, lev, dom) return list(map(per, R))
[docs] def resultant(f, g, includePRS=False): """Computes resultant of ``f`` and ``g`` via PRS. """ lev, dom, per, F, G = f.unify(g) if includePRS: res, R = dmp_resultant(F, G, lev, dom, includePRS=includePRS) return per(res, kill=True), list(map(per, R)) return per(dmp_resultant(F, G, lev, dom), kill=True)
[docs] def discriminant(f): """Computes discriminant of ``f``. """ return f.per(dmp_discriminant(f.rep, f.lev, f.dom), kill=True)
[docs] def cofactors(f, g): """Returns GCD of ``f`` and ``g`` and their cofactors. """ lev, dom, per, F, G = f.unify(g) h, cff, cfg = dmp_inner_gcd(F, G, lev, dom) return per(h), per(cff), per(cfg)
[docs] def gcd(f, g): """Returns polynomial GCD of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_gcd(F, G, lev, dom))
[docs] def lcm(f, g): """Returns polynomial LCM of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_lcm(F, G, lev, dom))
[docs] def cancel(f, g, include=True): """Cancel common factors in a rational function ``f/g``. """ lev, dom, per, F, G = f.unify(g) if include: F, G = dmp_cancel(F, G, lev, dom, include=True) else: cF, cG, F, G = dmp_cancel(F, G, lev, dom, include=False) F, G = per(F), per(G) if include: return F, G else: return cF, cG, F, G
[docs] def trunc(f, p): """Reduce ``f`` modulo a constant ``p``. """ return f.per(dmp_ground_trunc(f.rep, f.dom.convert(p), f.lev, f.dom))
[docs] def monic(f): """Divides all coefficients by ``LC(f)``. """ return f.per(dmp_ground_monic(f.rep, f.lev, f.dom))
[docs] def content(f): """Returns GCD of polynomial coefficients. """ return dmp_ground_content(f.rep, f.lev, f.dom)
[docs] def primitive(f): """Returns content and a primitive form of ``f``. """ cont, F = dmp_ground_primitive(f.rep, f.lev, f.dom) return cont, f.per(F)
[docs] def compose(f, g): """Computes functional composition of ``f`` and ``g``. """ lev, dom, per, F, G = f.unify(g) return per(dmp_compose(F, G, lev, dom))
[docs] def decompose(f): """Computes functional decomposition of ``f``. """ if not f.lev: return list(map(f.per, dup_decompose(f.rep, f.dom))) else: raise ValueError('univariate polynomial expected')
[docs] def shift(f, a): """Efficiently compute Taylor shift ``f(x + a)``. """ if not f.lev: return f.per(dup_shift(f.rep, f.dom.convert(a), f.dom)) else: raise ValueError('univariate polynomial expected')
[docs] def transform(f, p, q): """Evaluate functional transformation ``q**n * f(p/q)``.""" if f.lev: raise ValueError('univariate polynomial expected') lev, dom, per, P, Q = p.unify(q) lev, dom, per, F, P = f.unify(per(P, dom, lev)) lev, dom, per, F, Q = per(F, dom, lev).unify(per(Q, dom, lev)) if not lev: return per(dup_transform(F, P, Q, dom)) else: raise ValueError('univariate polynomial expected')
[docs] def sturm(f): """Computes the Sturm sequence of ``f``. """ if not f.lev: return list(map(f.per, dup_sturm(f.rep, f.dom))) else: raise ValueError('univariate polynomial expected')
[docs] def gff_list(f): """Computes greatest factorial factorization of ``f``. """ if not f.lev: return [ (f.per(g), k) for g, k in dup_gff_list(f.rep, f.dom) ] else: raise ValueError('univariate polynomial expected')
[docs] def norm(f): """Computes ``Norm(f)``.""" r = dmp_norm(f.rep, f.lev, f.dom) return f.per(r, dom=f.dom.dom)
[docs] def sqf_norm(f): """Computes square-free norm of ``f``. """ s, g, r = dmp_sqf_norm(f.rep, f.lev, f.dom) return s, f.per(g), f.per(r, dom=f.dom.dom)
[docs] def sqf_part(f): """Computes square-free part of ``f``. """ return f.per(dmp_sqf_part(f.rep, f.lev, f.dom))
[docs] def sqf_list(f, all=False): """Returns a list of square-free factors of ``f``. """ coeff, factors = dmp_sqf_list(f.rep, f.lev, f.dom, all) return coeff, [ (f.per(g), k) for g, k in factors ]
[docs] def sqf_list_include(f, all=False): """Returns a list of square-free factors of ``f``. """ factors = dmp_sqf_list_include(f.rep, f.lev, f.dom, all) return [ (f.per(g), k) for g, k in factors ]
[docs] def factor_list(f): """Returns a list of irreducible factors of ``f``. """ coeff, factors = dmp_factor_list(f.rep, f.lev, f.dom) return coeff, [ (f.per(g), k) for g, k in factors ]
[docs] def factor_list_include(f): """Returns a list of irreducible factors of ``f``. """ factors = dmp_factor_list_include(f.rep, f.lev, f.dom) return [ (f.per(g), k) for g, k in factors ]
[docs] def intervals(f, all=False, eps=None, inf=None, sup=None, fast=False, sqf=False): """Compute isolating intervals for roots of ``f``. """ if not f.lev: if not all: if not sqf: return dup_isolate_real_roots(f.rep, f.dom, eps=eps, inf=inf, sup=sup, fast=fast) else: return dup_isolate_real_roots_sqf(f.rep, f.dom, eps=eps, inf=inf, sup=sup, fast=fast) else: if not sqf: return dup_isolate_all_roots(f.rep, f.dom, eps=eps, inf=inf, sup=sup, fast=fast) else: return dup_isolate_all_roots_sqf(f.rep, f.dom, eps=eps, inf=inf, sup=sup, fast=fast) else: raise PolynomialError( "can't isolate roots of a multivariate polynomial")
[docs] def refine_root(f, s, t, eps=None, steps=None, fast=False): """ Refine an isolating interval to the given precision. ``eps`` should be a rational number. """ if not f.lev: return dup_refine_real_root(f.rep, s, t, f.dom, eps=eps, steps=steps, fast=fast) else: raise PolynomialError( "can't refine a root of a multivariate polynomial")
[docs] def count_real_roots(f, inf=None, sup=None): """Return the number of real roots of ``f`` in ``[inf, sup]``. """ return dup_count_real_roots(f.rep, f.dom, inf=inf, sup=sup)
[docs] def count_complex_roots(f, inf=None, sup=None): """Return the number of complex roots of ``f`` in ``[inf, sup]``. """ return dup_count_complex_roots(f.rep, f.dom, inf=inf, sup=sup)
@property def is_zero(f): """Returns ``True`` if ``f`` is a zero polynomial. """ return dmp_zero_p(f.rep, f.lev) @property def is_one(f): """Returns ``True`` if ``f`` is a unit polynomial. """ return dmp_one_p(f.rep, f.lev, f.dom) @property def is_ground(f): """Returns ``True`` if ``f`` is an element of the ground domain. """ return dmp_ground_p(f.rep, None, f.lev) @property def is_sqf(f): """Returns ``True`` if ``f`` is a square-free polynomial. """ return dmp_sqf_p(f.rep, f.lev, f.dom) @property def is_monic(f): """Returns ``True`` if the leading coefficient of ``f`` is one. """ return f.dom.is_one(dmp_ground_LC(f.rep, f.lev, f.dom)) @property def is_primitive(f): """Returns ``True`` if the GCD of the coefficients of ``f`` is one. """ return f.dom.is_one(dmp_ground_content(f.rep, f.lev, f.dom)) @property def is_linear(f): """Returns ``True`` if ``f`` is linear in all its variables. """ return all(sum(monom) <= 1 for monom in dmp_to_dict(f.rep, f.lev, f.dom).keys()) @property def is_quadratic(f): """Returns ``True`` if ``f`` is quadratic in all its variables. """ return all(sum(monom) <= 2 for monom in dmp_to_dict(f.rep, f.lev, f.dom).keys()) @property def is_monomial(f): """Returns ``True`` if ``f`` is zero or has only one term. """ return len(f.to_dict()) <= 1 @property def is_homogeneous(f): """Returns ``True`` if ``f`` is a homogeneous polynomial. """ return f.homogeneous_order() is not None @property def is_irreducible(f): """Returns ``True`` if ``f`` has no factors over its domain. """ return dmp_irreducible_p(f.rep, f.lev, f.dom) @property def is_cyclotomic(f): """Returns ``True`` if ``f`` is a cyclotomic polynomial. """ if not f.lev: return dup_cyclotomic_p(f.rep, f.dom) else: return False def __abs__(f): return f.abs() def __neg__(f): return f.neg() def __add__(f, g): if not isinstance(g, DMP): try: g = f.per(dmp_ground(f.dom.convert(g), f.lev)) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: g = f.ring.convert(g) except (CoercionFailed, NotImplementedError): return NotImplemented return f.add(g) def __radd__(f, g): return f.__add__(g) def __sub__(f, g): if not isinstance(g, DMP): try: g = f.per(dmp_ground(f.dom.convert(g), f.lev)) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: g = f.ring.convert(g) except (CoercionFailed, NotImplementedError): return NotImplemented return f.sub(g) def __rsub__(f, g): return (-f).__add__(g) def __mul__(f, g): if isinstance(g, DMP): return f.mul(g) else: try: return f.mul_ground(g) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: return f.mul(f.ring.convert(g)) except (CoercionFailed, NotImplementedError): pass return NotImplemented def __div__(f, g): if isinstance(g, DMP): return f.exquo(g) else: try: return f.mul_ground(g) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: return f.exquo(f.ring.convert(g)) except (CoercionFailed, NotImplementedError): pass return NotImplemented def __rdiv__(f, g): if isinstance(g, DMP): return g.exquo(f) elif f.ring is not None: try: return f.ring.convert(g).exquo(f) except (CoercionFailed, NotImplementedError): pass return NotImplemented __truediv__ = __div__ __rtruediv__ = __rdiv__ def __rmul__(f, g): return f.__mul__(g) def __pow__(f, n): return f.pow(n) def __divmod__(f, g): return f.div(g) def __mod__(f, g): return f.rem(g) def __floordiv__(f, g): if isinstance(g, DMP): return f.quo(g) else: try: return f.quo_ground(g) except TypeError: return NotImplemented def __eq__(f, g): try: _, _, _, F, G = f.unify(g) if f.lev == g.lev: return F == G except UnificationFailed: pass return False def __ne__(f, g): return not f == g def eq(f, g, strict=False): if not strict: return f == g else: return f._strict_eq(g) def ne(f, g, strict=False): return not f.eq(g, strict=strict) def _strict_eq(f, g): return isinstance(g, f.__class__) and f.lev == g.lev \ and f.dom == g.dom \ and f.rep == g.rep def __lt__(f, g): _, _, _, F, G = f.unify(g) return F < G def __le__(f, g): _, _, _, F, G = f.unify(g) return F <= G def __gt__(f, g): _, _, _, F, G = f.unify(g) return F > G def __ge__(f, g): _, _, _, F, G = f.unify(g) return F >= G def __nonzero__(f): return not dmp_zero_p(f.rep, f.lev) __bool__ = __nonzero__
def init_normal_DMF(num, den, lev, dom): return DMF(dmp_normal(num, lev, dom), dmp_normal(den, lev, dom), dom, lev)
[docs]class DMF(PicklableWithSlots, CantSympify): """Dense Multivariate Fractions over `K`. """ __slots__ = ['num', 'den', 'lev', 'dom', 'ring'] def __init__(self, rep, dom, lev=None, ring=None): num, den, lev = self._parse(rep, dom, lev) num, den = dmp_cancel(num, den, lev, dom) self.num = num self.den = den self.lev = lev self.dom = dom self.ring = ring @classmethod def new(cls, rep, dom, lev=None, ring=None): num, den, lev = cls._parse(rep, dom, lev) obj = object.__new__(cls) obj.num = num obj.den = den obj.lev = lev obj.dom = dom obj.ring = ring return obj @classmethod def _parse(cls, rep, dom, lev=None): if type(rep) is tuple: num, den = rep if lev is not None: if type(num) is dict: num = dmp_from_dict(num, lev, dom) if type(den) is dict: den = dmp_from_dict(den, lev, dom) else: num, num_lev = dmp_validate(num) den, den_lev = dmp_validate(den) if num_lev == den_lev: lev = num_lev else: raise ValueError('inconsistent number of levels') if dmp_zero_p(den, lev): raise ZeroDivisionError('fraction denominator') if dmp_zero_p(num, lev): den = dmp_one(lev, dom) else: if dmp_negative_p(den, lev, dom): num = dmp_neg(num, lev, dom) den = dmp_neg(den, lev, dom) else: num = rep if lev is not None: if type(num) is dict: num = dmp_from_dict(num, lev, dom) elif type(num) is not list: num = dmp_ground(dom.convert(num), lev) else: num, lev = dmp_validate(num) den = dmp_one(lev, dom) return num, den, lev def __repr__(f): return "%s((%s, %s), %s, %s)" % (f.__class__.__name__, f.num, f.den, f.dom, f.ring) def __hash__(f): return hash((f.__class__.__name__, dmp_to_tuple(f.num, f.lev), dmp_to_tuple(f.den, f.lev), f.lev, f.dom, f.ring))
[docs] def poly_unify(f, g): """Unify a multivariate fraction and a polynomial. """ if not isinstance(g, DMP) or f.lev != g.lev: raise UnificationFailed("can't unify %s with %s" % (f, g)) if f.dom == g.dom and f.ring == g.ring: return (f.lev, f.dom, f.per, (f.num, f.den), g.rep) else: lev, dom = f.lev, f.dom.unify(g.dom) ring = f.ring if g.ring is not None: if ring is not None: ring = ring.unify(g.ring) else: ring = g.ring F = (dmp_convert(f.num, lev, f.dom, dom), dmp_convert(f.den, lev, f.dom, dom)) G = dmp_convert(g.rep, lev, g.dom, dom) def per(num, den, cancel=True, kill=False, lev=lev): if kill: if not lev: return num/den else: lev = lev - 1 if cancel: num, den = dmp_cancel(num, den, lev, dom) return f.__class__.new((num, den), dom, lev, ring=ring) return lev, dom, per, F, G
[docs] def frac_unify(f, g): """Unify representations of two multivariate fractions. """ if not isinstance(g, DMF) or f.lev != g.lev: raise UnificationFailed("can't unify %s with %s" % (f, g)) if f.dom == g.dom and f.ring == g.ring: return (f.lev, f.dom, f.per, (f.num, f.den), (g.num, g.den)) else: lev, dom = f.lev, f.dom.unify(g.dom) ring = f.ring if g.ring is not None: if ring is not None: ring = ring.unify(g.ring) else: ring = g.ring F = (dmp_convert(f.num, lev, f.dom, dom), dmp_convert(f.den, lev, f.dom, dom)) G = (dmp_convert(g.num, lev, g.dom, dom), dmp_convert(g.den, lev, g.dom, dom)) def per(num, den, cancel=True, kill=False, lev=lev): if kill: if not lev: return num/den else: lev = lev - 1 if cancel: num, den = dmp_cancel(num, den, lev, dom) return f.__class__.new((num, den), dom, lev, ring=ring) return lev, dom, per, F, G
[docs] def per(f, num, den, cancel=True, kill=False, ring=None): """Create a DMF out of the given representation. """ lev, dom = f.lev, f.dom if kill: if not lev: return num/den else: lev -= 1 if cancel: num, den = dmp_cancel(num, den, lev, dom) if ring is None: ring = f.ring return f.__class__.new((num, den), dom, lev, ring=ring)
[docs] def half_per(f, rep, kill=False): """Create a DMP out of the given representation. """ lev = f.lev if kill: if not lev: return rep else: lev -= 1 return DMP(rep, f.dom, lev)
@classmethod def zero(cls, lev, dom, ring=None): return cls.new(0, dom, lev, ring=ring) @classmethod def one(cls, lev, dom, ring=None): return cls.new(1, dom, lev, ring=ring)
[docs] def numer(f): """Returns the numerator of ``f``. """ return f.half_per(f.num)
[docs] def denom(f): """Returns the denominator of ``f``. """ return f.half_per(f.den)
[docs] def cancel(f): """Remove common factors from ``f.num`` and ``f.den``. """ return f.per(f.num, f.den)
[docs] def neg(f): """Negate all coefficients in ``f``. """ return f.per(dmp_neg(f.num, f.lev, f.dom), f.den, cancel=False)
[docs] def add(f, g): """Add two multivariate fractions ``f`` and ``g``. """ if isinstance(g, DMP): lev, dom, per, (F_num, F_den), G = f.poly_unify(g) num, den = dmp_add_mul(F_num, F_den, G, lev, dom), F_den else: lev, dom, per, F, G = f.frac_unify(g) (F_num, F_den), (G_num, G_den) = F, G num = dmp_add(dmp_mul(F_num, G_den, lev, dom), dmp_mul(F_den, G_num, lev, dom), lev, dom) den = dmp_mul(F_den, G_den, lev, dom) return per(num, den)
[docs] def sub(f, g): """Subtract two multivariate fractions ``f`` and ``g``. """ if isinstance(g, DMP): lev, dom, per, (F_num, F_den), G = f.poly_unify(g) num, den = dmp_sub_mul(F_num, F_den, G, lev, dom), F_den else: lev, dom, per, F, G = f.frac_unify(g) (F_num, F_den), (G_num, G_den) = F, G num = dmp_sub(dmp_mul(F_num, G_den, lev, dom), dmp_mul(F_den, G_num, lev, dom), lev, dom) den = dmp_mul(F_den, G_den, lev, dom) return per(num, den)
[docs] def mul(f, g): """Multiply two multivariate fractions ``f`` and ``g``. """ if isinstance(g, DMP): lev, dom, per, (F_num, F_den), G = f.poly_unify(g) num, den = dmp_mul(F_num, G, lev, dom), F_den else: lev, dom, per, F, G = f.frac_unify(g) (F_num, F_den), (G_num, G_den) = F, G num = dmp_mul(F_num, G_num, lev, dom) den = dmp_mul(F_den, G_den, lev, dom) return per(num, den)
[docs] def pow(f, n): """Raise ``f`` to a non-negative power ``n``. """ if isinstance(n, int): return f.per(dmp_pow(f.num, n, f.lev, f.dom), dmp_pow(f.den, n, f.lev, f.dom), cancel=False) else: raise TypeError("``int`` expected, got %s" % type(n))
[docs] def quo(f, g): """Computes quotient of fractions ``f`` and ``g``. """ if isinstance(g, DMP): lev, dom, per, (F_num, F_den), G = f.poly_unify(g) num, den = F_num, dmp_mul(F_den, G, lev, dom) else: lev, dom, per, F, G = f.frac_unify(g) (F_num, F_den), (G_num, G_den) = F, G num = dmp_mul(F_num, G_den, lev, dom) den = dmp_mul(F_den, G_num, lev, dom) res = per(num, den) if f.ring is not None and res not in f.ring: from sympy.polys.polyerrors import ExactQuotientFailed raise ExactQuotientFailed(f, g, f.ring) return res
exquo = quo
[docs] def invert(f, check=True): """Computes inverse of a fraction ``f``. """ if check and f.ring is not None and not f.ring.is_unit(f): raise NotReversible(f, f.ring) res = f.per(f.den, f.num, cancel=False) return res
@property def is_zero(f): """Returns ``True`` if ``f`` is a zero fraction. """ return dmp_zero_p(f.num, f.lev) @property def is_one(f): """Returns ``True`` if ``f`` is a unit fraction. """ return dmp_one_p(f.num, f.lev, f.dom) and \ dmp_one_p(f.den, f.lev, f.dom) def __neg__(f): return f.neg() def __add__(f, g): if isinstance(g, (DMP, DMF)): return f.add(g) try: return f.add(f.half_per(g)) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: return f.add(f.ring.convert(g)) except (CoercionFailed, NotImplementedError): pass return NotImplemented def __radd__(f, g): return f.__add__(g) def __sub__(f, g): if isinstance(g, (DMP, DMF)): return f.sub(g) try: return f.sub(f.half_per(g)) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: return f.sub(f.ring.convert(g)) except (CoercionFailed, NotImplementedError): pass return NotImplemented def __rsub__(f, g): return (-f).__add__(g) def __mul__(f, g): if isinstance(g, (DMP, DMF)): return f.mul(g) try: return f.mul(f.half_per(g)) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: return f.mul(f.ring.convert(g)) except (CoercionFailed, NotImplementedError): pass return NotImplemented def __rmul__(f, g): return f.__mul__(g) def __pow__(f, n): return f.pow(n) def __div__(f, g): if isinstance(g, (DMP, DMF)): return f.quo(g) try: return f.quo(f.half_per(g)) except TypeError: return NotImplemented except (CoercionFailed, NotImplementedError): if f.ring is not None: try: return f.quo(f.ring.convert(g)) except (CoercionFailed, NotImplementedError): pass return NotImplemented def __rdiv__(self, g): r = self.invert(check=False)*g if self.ring and r not in self.ring: from sympy.polys.polyerrors import ExactQuotientFailed raise ExactQuotientFailed(g, self, self.ring) return r __truediv__ = __div__ __rtruediv__ = __rdiv__ def __eq__(f, g): try: if isinstance(g, DMP): _, _, _, (F_num, F_den), G = f.poly_unify(g) if f.lev == g.lev: return dmp_one_p(F_den, f.lev, f.dom) and F_num == G else: _, _, _, F, G = f.frac_unify(g) if f.lev == g.lev: return F == G except UnificationFailed: pass return False def __ne__(f, g): try: if isinstance(g, DMP): _, _, _, (F_num, F_den), G = f.poly_unify(g) if f.lev == g.lev: return not (dmp_one_p(F_den, f.lev, f.dom) and F_num == G) else: _, _, _, F, G = f.frac_unify(g) if f.lev == g.lev: return F != G except UnificationFailed: pass return True def __lt__(f, g): _, _, _, F, G = f.frac_unify(g) return F < G def __le__(f, g): _, _, _, F, G = f.frac_unify(g) return F <= G def __gt__(f, g): _, _, _, F, G = f.frac_unify(g) return F > G def __ge__(f, g): _, _, _, F, G = f.frac_unify(g) return F >= G def __nonzero__(f): return not dmp_zero_p(f.num, f.lev) __bool__ = __nonzero__
def init_normal_ANP(rep, mod, dom): return ANP(dup_normal(rep, dom), dup_normal(mod, dom), dom)
[docs]class ANP(PicklableWithSlots, CantSympify): """Dense Algebraic Number Polynomials over a field. """ __slots__ = ['rep', 'mod', 'dom'] def __init__(self, rep, mod, dom): if type(rep) is dict: self.rep = dup_from_dict(rep, dom) else: if type(rep) is not list: rep = [dom.convert(rep)] self.rep = dup_strip(rep) if isinstance(mod, DMP): self.mod = mod.rep else: if type(mod) is dict: self.mod = dup_from_dict(mod, dom) else: self.mod = dup_strip(mod) self.dom = dom def __repr__(f): return "%s(%s, %s, %s)" % (f.__class__.__name__, f.rep, f.mod, f.dom) def __hash__(f): return hash((f.__class__.__name__, f.to_tuple(), dmp_to_tuple(f.mod, 0), f.dom))
[docs] def unify(f, g): """Unify representations of two algebraic numbers. """ if not isinstance(g, ANP) or f.mod != g.mod: raise UnificationFailed("can't unify %s with %s" % (f, g)) if f.dom == g.dom: return f.dom, f.per, f.rep, g.rep, f.mod else: dom = f.dom.unify(g.dom) F = dup_convert(f.rep, f.dom, dom) G = dup_convert(g.rep, g.dom, dom) if dom != f.dom and dom != g.dom: mod = dup_convert(f.mod, f.dom, dom) else: if dom == f.dom: mod = f.mod else: mod = g.mod per = lambda rep: ANP(rep, mod, dom) return dom, per, F, G, mod
def per(f, rep, mod=None, dom=None): return ANP(rep, mod or f.mod, dom or f.dom) @classmethod def zero(cls, mod, dom): return ANP(0, mod, dom) @classmethod def one(cls, mod, dom): return ANP(1, mod, dom)
[docs] def to_dict(f): """Convert ``f`` to a dict representation with native coefficients. """ return dmp_to_dict(f.rep, 0, f.dom)
[docs] def to_sympy_dict(f): """Convert ``f`` to a dict representation with SymPy coefficients. """ rep = dmp_to_dict(f.rep, 0, f.dom) for k, v in rep.items(): rep[k] = f.dom.to_sympy(v) return rep
[docs] def to_list(f): """Convert ``f`` to a list representation with native coefficients. """ return f.rep
[docs] def to_sympy_list(f): """Convert ``f`` to a list representation with SymPy coefficients. """ return [ f.dom.to_sympy(c) for c in f.rep ]
[docs] def to_tuple(f): """ Convert ``f`` to a tuple representation with native coefficients. This is needed for hashing. """ return dmp_to_tuple(f.rep, 0)
@classmethod def from_list(cls, rep, mod, dom): return ANP(dup_strip(list(map(dom.convert, rep))), mod, dom) def neg(f): return f.per(dup_neg(f.rep, f.dom)) def add(f, g): dom, per, F, G, mod = f.unify(g) return per(dup_add(F, G, dom)) def sub(f, g): dom, per, F, G, mod = f.unify(g) return per(dup_sub(F, G, dom)) def mul(f, g): dom, per, F, G, mod = f.unify(g) return per(dup_rem(dup_mul(F, G, dom), mod, dom))
[docs] def pow(f, n): """Raise ``f`` to a non-negative power ``n``. """ if isinstance(n, int): if n < 0: F, n = dup_invert(f.rep, f.mod, f.dom), -n else: F = f.rep return f.per(dup_rem(dup_pow(F, n, f.dom), f.mod, f.dom)) else: raise TypeError("``int`` expected, got %s" % type(n))
def div(f, g): dom, per, F, G, mod = f.unify(g) return (per(dup_rem(dup_mul(F, dup_invert(G, mod, dom), dom), mod, dom)), f.zero(mod, dom)) def rem(f, g): dom, _, _, G, mod = f.unify(g) s, h = dup_half_gcdex(G, mod, dom) if h == [dom.one]: return f.zero(mod, dom) else: raise NotInvertible("zero divisor") def quo(f, g): dom, per, F, G, mod = f.unify(g) return per(dup_rem(dup_mul(F, dup_invert(G, mod, dom), dom), mod, dom)) exquo = quo
[docs] def LC(f): """Returns the leading coefficient of ``f``. """ return dup_LC(f.rep, f.dom)
[docs] def TC(f): """Returns the trailing coefficient of ``f``. """ return dup_TC(f.rep, f.dom)
@property def is_zero(f): """Returns ``True`` if ``f`` is a zero algebraic number. """ return not f @property def is_one(f): """Returns ``True`` if ``f`` is a unit algebraic number. """ return f.rep == [f.dom.one] @property def is_ground(f): """Returns ``True`` if ``f`` is an element of the ground domain. """ return not f.rep or len(f.rep) == 1 def __neg__(f): return f.neg() def __add__(f, g): if isinstance(g, ANP): return f.add(g) else: try: return f.add(f.per(g)) except (CoercionFailed, TypeError): return NotImplemented def __radd__(f, g): return f.__add__(g) def __sub__(f, g): if isinstance(g, ANP): return f.sub(g) else: try: return f.sub(f.per(g)) except (CoercionFailed, TypeError): return NotImplemented def __rsub__(f, g): return (-f).__add__(g) def __mul__(f, g): if isinstance(g, ANP): return f.mul(g) else: try: return f.mul(f.per(g)) except (CoercionFailed, TypeError): return NotImplemented def __rmul__(f, g): return f.__mul__(g) def __pow__(f, n): return f.pow(n) def __divmod__(f, g): return f.div(g) def __mod__(f, g): return f.rem(g) def __div__(f, g): if isinstance(g, ANP): return f.quo(g) else: try: return f.quo(f.per(g)) except (CoercionFailed, TypeError): return NotImplemented __truediv__ = __div__ def __eq__(f, g): try: _, _, F, G, _ = f.unify(g) return F == G except UnificationFailed: return False def __ne__(f, g): try: _, _, F, G, _ = f.unify(g) return F != G except UnificationFailed: return True def __lt__(f, g): _, _, F, G, _ = f.unify(g) return F < G def __le__(f, g): _, _, F, G, _ = f.unify(g) return F <= G def __gt__(f, g): _, _, F, G, _ = f.unify(g) return F > G def __ge__(f, g): _, _, F, G, _ = f.unify(g) return F >= G def __nonzero__(f): return bool(f.rep) __bool__ = __nonzero__