def primerange(self, a, b): """Generate all prime numbers in the range [a, b). Examples ======== >>> from sympy import sieve >>> print([i for i in sieve.primerange(7, 18)]) [7, 11, 13, 17] """ from sympy.functions.elementary.integers import ceiling # wrapping ceiling in int will raise an error if there was a problem # determining whether the expression was exactly an integer or not a = max(2, int(ceiling(a))) b = int(ceiling(b)) if a >= b: return self.extend(b) i = self.search(a)[1] maxi = len(self._list) + 1 while i < maxi: p = self._list[i - 1] if p < b: yield p i += 1 else: return
def test_issue_8413(): x = Symbol('x', real=True) # we can't evaluate in general because non-reals are not # comparable: Min(floor(3.2 + I), 3.2 + I) -> ValueError assert Min(floor(x), x) == floor(x) assert Min(ceiling(x), x) == x assert Max(floor(x), x) == x assert Max(ceiling(x), x) == ceiling(x)
def _intersect(self, other): from sympy.functions.elementary.integers import floor, ceiling from sympy.functions.elementary.miscellaneous import Min, Max if other.is_Interval: osup = other.sup oinf = other.inf # if other is [0, 10) we can only go up to 9 if osup.is_integer and other.right_open: osup -= 1 if oinf.is_integer and other.left_open: oinf += 1 # Take the most restrictive of the bounds set by the two sets # round inwards inf = ceiling(Max(self.inf, oinf)) sup = floor(Min(self.sup, osup)) # if we are off the sequence, get back on off = (inf - self.inf) % self.step if off: inf += self.step - off return Range(inf, sup + 1, self.step) if other == S.Naturals: return self._intersect(Interval(1, S.Infinity)) if other == S.Integers: return self return None
def __new__(cls, *args): from sympy.functions.elementary.integers import ceiling # expand range slc = slice(*args) start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: start, stop, step = [w if w in [S.NegativeInfinity, S.Infinity] else S(as_int(w)) for w in (start, stop, step)] except ValueError: raise ValueError("Inputs to Range must be Integer Valued\n" + "Use ImageSets of Ranges for other cases") if not step.is_finite: raise ValueError("Infinite step is not allowed") if start == stop: return S.EmptySet n = ceiling((stop - start)/step) if n <= 0: return S.EmptySet # normalize args: regardless of how they are entered they will show # canonically as Range(inf, sup, step) with step > 0 if n.is_finite: start, stop = sorted((start, start + (n - 1)*step)) else: start, stop = sorted((start, stop - step)) step = abs(step) if (start, stop) == (S.NegativeInfinity, S.Infinity): raise ValueError("Both the start and end value of " "Range cannot be unbounded") else: return Basic.__new__(cls, start, stop + step, step)
def search(self, n): """Return the indices i, j of the primes that bound n. If n is prime then i == j. Although n can be an expression, if ceiling cannot convert it to an integer then an n error will be raised. Examples ======== >>> from sympy import sieve >>> sieve.search(25) (9, 10) >>> sieve.search(23) (9, 9) """ from sympy.functions.elementary.integers import ceiling # wrapping ceiling in int will raise an error if there was a problem # determining whether the expression was exactly an integer or not test = int(ceiling(n)) n = int(n) if n < 2: raise ValueError("n should be >= 2 but got: %s" % n) if n > self._list[-1]: self.extend(n) b = bisect(self._list, n) if self._list[b - 1] == test: return b, b else: return b, b + 1
def eval(cls, ar, period): # Our strategy is to evaluate the argument on the Riemann surface of the # logarithm, and then reduce. # NOTE evidently this means it is a rather bad idea to use this with # period != 2*pi and non-polar numbers. if not period.is_positive: return None if period == oo and isinstance(ar, principal_branch): return periodic_argument(*ar.args) if isinstance(ar, polar_lift) and period >= 2*pi: return periodic_argument(ar.args[0], period) if ar.is_Mul: newargs = [x for x in ar.args if not x.is_positive] if len(newargs) != len(ar.args): return periodic_argument(Mul(*newargs), period) unbranched = cls._getunbranched(ar) if unbranched is None: return None if unbranched.has(periodic_argument, atan2, atan): return None if period == oo: return unbranched if period != oo: n = ceiling(unbranched/period - S(1)/2)*period if not n.has(ceiling): return unbranched - n
def mobiusrange(self, a, b): """Generate all mobius numbers for the range [a, b). Parameters ========== a : integer First number in range b : integer First number outside of range Examples ======== >>> from sympy import sieve >>> print([i for i in sieve.mobiusrange(7, 18)]) [-1, 0, 0, 1, -1, 0, -1, 1, 1, 0, -1] """ from sympy.functions.elementary.integers import ceiling # wrapping ceiling in as_int will raise an error if there was a problem # determining whether the expression was exactly an integer or not a = max(1, as_int(ceiling(a))) b = as_int(ceiling(b)) n = len(self._mlist) if a >= b: return elif b <= n: for i in range(a, b): yield self._mlist[i] else: self._mlist += _azeros(b - n) for i in range(1, n): mi = self._mlist[i] startindex = (n + i - 1) // i * i for j in range(startindex, b, i): self._mlist[j] -= mi if i >= a: yield mi for i in range(n, b): mi = self._mlist[i] for j in range(2 * i, b, i): self._mlist[j] -= mi if i >= a: yield mi
def _intersect(self, other): from sympy.functions.elementary.integers import floor, ceiling if other is Interval(S.NegativeInfinity, S.Infinity) or other is S.Reals: return self elif other.is_Interval: s = Range(ceiling(other.left), floor(other.right) + 1) return s.intersect(other) # take out endpoints if open interval return None
def _eval_evalf(self, prec): z, period = self.args if period == oo: unbranched = periodic_argument._getunbranched(z) if unbranched is None: return self return unbranched._eval_evalf(prec) ub = periodic_argument(z, oo)._eval_evalf(prec) return (ub - ceiling(ub/period - S(1)/2)*period)._eval_evalf(prec)
def _eval_aseries(self, n, args0, x, logx): from sympy import Order if args0[1] != oo or not \ (self.args[0].is_Integer and self.args[0].is_nonnegative): return super(polygamma, self)._eval_aseries(n, args0, x, logx) z = self.args[1] N = self.args[0] if N == 0: # digamma function series # Abramowitz & Stegun, p. 259, 6.3.18 r = log(z) - 1/(2*z) o = None if n < 2: o = Order(1/z, x) else: m = ceiling((n + 1)//2) l = [bernoulli(2*k) / (2*k*z**(2*k)) for k in range(1, m)] r -= Add(*l) o = Order(1/z**(2*m), x) return r._eval_nseries(x, n, logx) + o else: # proper polygamma function # Abramowitz & Stegun, p. 260, 6.4.10 # We return terms to order higher than O(x**n) on purpose # -- otherwise we would not be able to return any terms for # quite a long time! fac = gamma(N) e0 = fac + N*fac/(2*z) m = ceiling((n + 1)//2) for k in range(1, m): fac = fac*(2*k + N - 1)*(2*k + N - 2) / ((2*k)*(2*k - 1)) e0 += bernoulli(2*k)*fac/z**(2*k) o = Order(1/z**(2*m), x) if n == 0: o = Order(1/z, x) elif n == 1: o = Order(1/z**2, x) r = e0._eval_nseries(z, n, logx) + o return (-1 * (-1/z)**N * r)._eval_nseries(x, n, logx)
def totientrange(self, a, b): """Generate all totient numbers for the range [a, b). Examples ======== >>> from sympy import sieve >>> print([i for i in sieve.totientrange(7, 18)]) [6, 4, 6, 4, 10, 4, 12, 6, 8, 8, 16] """ from sympy.functions.elementary.integers import ceiling # wrapping ceiling in as_int will raise an error if there was a problem # determining whether the expression was exactly an integer or not a = max(1, as_int(ceiling(a))) b = as_int(ceiling(b)) n = len(self._tlist) if a >= b: return elif b <= n: for i in range(a, b): yield self._tlist[i] else: self._tlist += _arange(n, b) for i in range(1, n): ti = self._tlist[i] startindex = (n + i - 1) // i * i for j in range(startindex, b, i): self._tlist[j] -= ti if i >= a: yield ti for i in range(n, b): ti = self._tlist[i] for j in range(2 * i, b, i): self._tlist[j] -= ti if i >= a: yield ti
def prevprime(n): """ Return the largest prime smaller than n. Notes ===== Potential primes are located at 6*j +/- 1. This property is used during searching. >>> from sympy import prevprime >>> [(i, prevprime(i)) for i in range(10, 15)] [(10, 7), (11, 7), (12, 11), (13, 11), (14, 13)] See Also ======== nextprime : Return the ith prime greater than n primerange : Generates all primes in a given range """ from sympy.functions.elementary.integers import ceiling # wrapping ceiling in int will raise an error if there was a problem # determining whether the expression was exactly an integer or not n = int(ceiling(n)) if n < 3: raise ValueError("no preceding primes") if n < 8: return {3: 2, 4: 3, 5: 3, 6: 5, 7: 5}[n] if n <= sieve._list[-1]: l, u = sieve.search(n) if l == u: return sieve[l-1] else: return sieve[l] nn = 6*(n//6) if n - nn <= 1: n = nn - 1 if isprime(n): return n n -= 4 else: n = nn + 1 while 1: if isprime(n): return n n -= 2 if isprime(n): return n n -= 4
def _eval_aseries(self, n, args0, x, logx): from sympy import Order if args0[0] != oo: return super(loggamma, self)._eval_aseries(n, args0, x, logx) z = self.args[0] m = min(n, ceiling((n + S(1))/2)) r = log(z)*(z - S(1)/2) - z + log(2*pi)/2 l = [bernoulli(2*k) / (2*k*(2*k - 1)*z**(2*k - 1)) for k in range(1, m)] o = None if m == 0: o = Order(1, x) else: o = Order(1/z**(2*m - 1), x) # It is very inefficient to first add the order and then do the nseries return (r + Add(*l))._eval_nseries(x, n, logx) + o
def __new__(cls, *args): from sympy.functions.elementary.integers import ceiling if len(args) == 1: if isinstance(args[0], range if PY3 else xrange): args = args[0].__reduce__()[1] # use pickle method # expand range slc = slice(*args) if slc.step == 0: raise ValueError("step cannot be 0") start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: start, stop, step = [ w if w in [S.NegativeInfinity, S.Infinity] else sympify(as_int(w)) for w in (start, stop, step)] except ValueError: raise ValueError(filldedent(''' Finite arguments to Range must be integers; `imageset` can define other cases, e.g. use `imageset(i, i/10, Range(3))` to give [0, 1/10, 1/5].''')) if not step.is_Integer: raise ValueError(filldedent(''' Ranges must have a literal integer step.''')) if all(i.is_infinite for i in (start, stop)): if start == stop: # canonical null handled below start = stop = S.One else: raise ValueError(filldedent(''' Either the start or end value of the Range must be finite.''')) if start.is_infinite: end = stop else: ref = start if start.is_finite else stop n = ceiling((stop - ref)/step) if n <= 0: # null Range start = end = 0 step = 1 else: end = ref + n*step return Basic.__new__(cls, start, end, step)
def intersection_sets(a, b): # noqa:F811 from sympy.functions.elementary.integers import floor, ceiling if not all(i.is_number for i in b.args[:2]): return # In case of null Range, return an EmptySet. if a.size == 0: return S.EmptySet # trim down to self's size, and represent # as a Range with step 1. start = ceiling(max(b.inf, a.inf)) if start not in b: start += 1 end = floor(min(b.sup, a.sup)) if end not in b: end -= 1 return intersection_sets(a, Range(start, end + 1))
def _eval_aseries(self, n, args0, x, logx): from sympy import Order if args0[0] != oo: return super(loggamma, self)._eval_aseries(n, args0, x, logx) z = self.args[0] m = min(n, ceiling((n + S(1)) / 2)) r = log(z) * (z - S(1) / 2) - z + log(2 * pi) / 2 l = [ bernoulli(2 * k) / (2 * k * (2 * k - 1) * z**(2 * k - 1)) for k in range(1, m) ] o = None if m == 0: o = Order(1, x) else: o = Order(1 / z**(2 * m - 1), x) # It is very inefficient to first add the order and then do the nseries return (r + Add(*l))._eval_nseries(x, n, logx) + o
def _real_to_rational(expr, tolerance=None): """ Replace all reals in expr with rationals. >>> from sympy import nsimplify >>> from sympy.abc import x >>> nsimplify(.76 + .1*x**.5, rational=True) sqrt(x)/10 + 19/25 """ inf = Float('inf') p = expr reps = {} reduce_num = None if tolerance is not None and tolerance < 1: reduce_num = ceiling(1/tolerance) for float in p.atoms(Float): key = float if reduce_num is not None: r = Rational(float).limit_denominator(reduce_num) elif (tolerance is not None and tolerance >= 1 and float.is_Integer is False): r = Rational(tolerance*round(float/tolerance) ).limit_denominator(int(tolerance)) else: r = nsimplify(float, rational=False) # e.g. log(3).n() -> log(3) instead of a Rational if float and not r: r = Rational(float) elif not r.is_Rational: if float == inf or float == -inf: r = S.ComplexInfinity elif float < 0: float = -float d = Pow(10, int((mpmath.log(float)/mpmath.log(10)))) r = -Rational(str(float/d))*d elif float > 0: d = Pow(10, int((mpmath.log(float)/mpmath.log(10)))) r = Rational(str(float/d))*d else: r = Integer(0) reps[key] = r return p.subs(reps, simultaneous=True)
def prevprime(n): """ Return the largest prime smaller than n. Notes ===== Potential primes are located at 6*j +/- 1. This property is used during searching. >>> from sympy import prevprime >>> [(i, prevprime(i)) for i in range(10, 15)] [(10, 7), (11, 7), (12, 11), (13, 11), (14, 13)] See Also ======== nextprime : Return the ith prime greater than n primerange : Generates all primes in a given range """ from sympy.functions.elementary.integers import ceiling # wrapping ceiling in int will raise an error if there was a problem # determining whether the expression was exactly an integer or not n = int(ceiling(n)) if n < 3: raise ValueError("no preceding primes") if n < 8: return {3: 2, 4: 3, 5: 3, 6: 5, 7: 5}[n] if n <= sieve._list[-1]: l, u = sieve.search(n) if l == u: return sieve[l - 1] else: return sieve[l] nn = 6 * (n // 6) if n - nn <= 1: n = nn - 1 if isprime(n): return n n -= 4 else: n = nn + 1 while 1: if isprime(n): return n n -= 2 if isprime(n): return n n -= 4
def __new__(cls, *args): # expand range slc = slice(*args) start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: start, stop, step = [S(as_int(w)) for w in (start, stop, step)] except ValueError: raise ValueError("Inputs to Range must be Integer Valued\n" + "Use ImageSets of Ranges for other cases") n = ceiling((stop - start)/step) if n <= 0: return S.EmptySet # normalize args: regardless of how they are entered they will show # canonically as Range(inf, sup, step) with step > 0 start, stop = sorted((start, start + (n - 1)*step)) step = abs(step) return Basic.__new__(cls, start, stop + step, step)
def intersection_sets(a, b): from sympy.functions.elementary.integers import floor, ceiling from sympy.functions.elementary.miscellaneous import Min, Max if not all(i.is_number for i in b.args[:2]): return # In case of null Range, return an EmptySet. if a.size == 0: return S.EmptySet # trim down to self's size, and represent # as a Range with step 1. start = ceiling(max(b.inf, a.inf)) if start not in b: start += 1 end = floor(min(b.sup, a.sup)) if end not in b: end -= 1 return intersection_sets(a, Range(start, end + 1))
def __new__(cls, *args): # expand range slc = slice(*args) start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: start, stop, step = [S(as_int(w)) for w in (start, stop, step)] except ValueError: raise ValueError("Inputs to Range must be Integer Valued\n" + "Use TransformationSets of Ranges for other cases") n = ceiling((stop - start)/step) if n <= 0: return S.EmptySet # normalize args: regardless of how they are entered they will show # canonically as Range(inf, sup, step) with step > 0 start, stop = sorted((start, start + (n - 1)*step)) step = abs(step) return Basic.__new__(cls, start, stop + step, step)
def _eval_nseries(self, x, n, logx, cdir=0): # NOTE Please see the comment at the beginning of this file, labelled # IMPORTANT. from sympy.functions.elementary.complexes import sign from sympy.functions.elementary.integers import ceiling from sympy.series.limits import limit from sympy.series.order import Order from sympy.simplify.powsimp import powsimp arg = self.exp arg_series = arg._eval_nseries(x, n=n, logx=logx) if arg_series.is_Order: return 1 + arg_series arg0 = limit(arg_series.removeO(), x, 0) if arg0 is S.NegativeInfinity: return Order(x**n, x) if arg0 is S.Infinity: return self # checking for indecisiveness/ sign terms in arg0 if any(isinstance(arg, (sign, ImaginaryUnit)) for arg in arg0.args): return self t = Dummy("t") nterms = n try: cf = Order(arg.as_leading_term(x, logx=logx), x).getn() except (NotImplementedError, PoleError): cf = 0 if cf and cf > 0: nterms = ceiling(n/cf) exp_series = exp(t)._taylor(t, nterms) r = exp(arg0)*exp_series.subs(t, arg_series - arg0) if cf and cf > 1: r += Order((arg_series - arg0)**n, x)/x**((cf-1)*n) else: r += Order((arg_series - arg0)**n, x) r = r.expand() r = powsimp(r, deep=True, combine='exp') # powsimp may introduce unexpanded (-1)**Rational; see PR #17201 simplerat = lambda x: x.is_Rational and x.q in [3, 4, 6] w = Wild('w', properties=[simplerat]) r = r.replace(S.NegativeOne**w, expand_complex(S.NegativeOne**w)) return r
def __new__(cls, *args): from sympy.functions.elementary.integers import ceiling if len(args) == 1: if isinstance(args[0], range if PY3 else xrange): args = args[0].__reduce__()[1] # use pickle method # expand range slc = slice(*args) start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: start, stop, step = [ w if w in [S.NegativeInfinity, S.Infinity] else sympify( as_int(w)) for w in (start, stop, step) ] except ValueError: raise ValueError("Inputs to Range must be Integer Valued\n" + "Use ImageSets of Ranges for other cases") if not step.is_finite: raise ValueError("Infinite step is not allowed") if start == stop: return S.EmptySet n = ceiling((stop - start) / step) if n <= 0: return S.EmptySet # normalize args: regardless of how they are entered they will show # canonically as Range(inf, sup, step) with step > 0 if n.is_finite: start, stop = sorted((start, start + (n - 1) * step)) else: start, stop = sorted((start, stop - step)) step = abs(step) if (start, stop) == (S.NegativeInfinity, S.Infinity): raise ValueError("Both the start and end value of " "Range cannot be unbounded") else: return Basic.__new__(cls, start, stop + step, step)
def __new__(cls, *args): from sympy.functions.elementary.integers import ceiling if len(args) == 1: if isinstance(args[0], range if PY3 else xrange): args = args[0].__reduce__()[1] # use pickle method # expand range slc = slice(*args) start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: start, stop, step = [w if w in [S.NegativeInfinity, S.Infinity] else sympify(as_int(w)) for w in (start, stop, step)] except ValueError: raise ValueError(filldedent(''' Inputs to Range must be integers; use ImageSets of Ranges for other cases, e.g. `ImageSet(Lambda(i, i/10), Range(2))` to give [0, .1].''')) if not step.is_finite: raise ValueError("Infinite step is not allowed") if start == stop: return S.EmptySet n = ceiling((stop - start)/step) if n <= 0: return S.EmptySet # normalize args: regardless of how they are entered they will show # canonically as Range(inf, sup, step) with step > 0 if n.is_finite: start, stop = sorted((start, start + (n - 1)*step)) else: start, stop = sorted((start, stop - step)) step = abs(step) if (start, stop) == (S.NegativeInfinity, S.Infinity): raise ValueError("Both the start and end value of " "Range cannot be unbounded") else: return Basic.__new__(cls, start, stop + step, step)
def test_evalf_integer_parts(): a = floor(log(8) / log(2) - exp(-1000), evaluate=False) b = floor(log(8) / log(2), evaluate=False) assert a.evalf() == 3 assert b.evalf() == 3 # equals, as a fallback, can still fail but it might succeed as here assert ceiling(10 * (sin(1)**2 + cos(1)**2)) == 10 assert int(floor(factorial(50)/E, evaluate=False).evalf(70)) == \ int(11188719610782480504630258070757734324011354208865721592720336800) assert int(ceiling(factorial(50)/E, evaluate=False).evalf(70)) == \ int(11188719610782480504630258070757734324011354208865721592720336801) assert int(floor(GoldenRatio**999 / sqrt(5) + S.Half).evalf(1000)) == fibonacci(999) assert int(floor(GoldenRatio**1000 / sqrt(5) + S.Half).evalf(1000)) == fibonacci(1000) assert ceiling(x).evalf(subs={x: 3}) == 3 assert ceiling(x).evalf(subs={x: 3 * I}) == 3.0 * I assert ceiling(x).evalf(subs={x: 2 + 3 * I}) == 2.0 + 3.0 * I assert ceiling(x).evalf(subs={x: 3.}) == 3 assert ceiling(x).evalf(subs={x: 3. * I}) == 3.0 * I assert ceiling(x).evalf(subs={x: 2. + 3 * I}) == 2.0 + 3.0 * I assert float((floor(1.5, evaluate=False) + 1 / 9).evalf()) == 1 + 1 / 9 assert float((floor(0.5, evaluate=False) + 20).evalf()) == 20 # issue 19991 n = 1169809367327212570704813632106852886389036911 r = 744723773141314414542111064094745678855643068 assert floor(n / (pi / 2)) == r assert floor(80782 * sqrt(2)) == 114242 # issue 20076 assert 260515 - floor(260515 / pi + 1 / 2) * pi == atan(tan(260515))
def _initialize_ith_poly(N, factor_base, i, g, B): """Initialization stage of ith poly. After we finish sieving 1`st polynomial here we quickly change to the next polynomial from which we will again start sieving. Suppose we generated ith sieve polynomial and now we want to generate (i + 1)th polynomial, where ``1 <= i <= 2**(j - 1) - 1`` where `j` is the number of prime factors of the coefficient `a` then this function can be used to go to the next polynomial. If ``i = 2**(j - 1) - 1`` then go to _initialize_first_polynomial stage. Parameters ========== N : number to be factored factor_base : factor_base primes i : integer denoting ith polynomial g : (i - 1)th polynomial B : array that stores a//q_l*gamma """ from sympy.functions.elementary.integers import ceiling v = 1 j = i while (j % 2 == 0): v += 1 j //= 2 if ceiling(i / (2**v)) % 2 == 1: neg_pow = -1 else: neg_pow = 1 b = g.b + 2 * neg_pow * B[v - 1] a = g.a g = SievePolynomial([a * a, 2 * a * b, b * b - N], a, b) for fb in factor_base: if a % fb.prime == 0: continue fb.soln1 = (fb.soln1 - neg_pow * fb.b_ainv[v - 1]) % fb.prime fb.soln2 = (fb.soln2 - neg_pow * fb.b_ainv[v - 1]) % fb.prime return g
def test_intrinsic_math1_codegen(): # not included: log10 from sympy.core.evalf import N from sympy.functions import ln from sympy.functions.elementary.exponential import log from sympy.functions.elementary.hyperbolic import (cosh, sinh, tanh) from sympy.functions.elementary.integers import (ceiling, floor) from sympy.functions.elementary.miscellaneous import sqrt from sympy.functions.elementary.trigonometric import (acos, asin, atan, cos, sin, tan) name_expr = [ ("test_fabs", abs(x)), ("test_acos", acos(x)), ("test_asin", asin(x)), ("test_atan", atan(x)), ("test_cos", cos(x)), ("test_cosh", cosh(x)), ("test_log", log(x)), ("test_ln", ln(x)), ("test_sin", sin(x)), ("test_sinh", sinh(x)), ("test_sqrt", sqrt(x)), ("test_tan", tan(x)), ("test_tanh", tanh(x)), ] numerical_tests = [] for name, expr in name_expr: for xval in 0.2, 0.5, 0.8: expected = N(expr.subs(x, xval)) numerical_tests.append((name, (xval, ), expected, 1e-14)) for lang, commands in valid_lang_commands: if lang.startswith("C"): name_expr_C = [("test_floor", floor(x)), ("test_ceil", ceiling(x))] else: name_expr_C = [] run_test("intrinsic_math1", name_expr + name_expr_C, numerical_tests, lang, commands)
def test_nested_floor_ceiling(): assert floor(-floor(ceiling(x**3)/y)) == -floor(ceiling(x**3)/y) assert ceiling(-floor(ceiling(x**3)/y)) == -floor(ceiling(x**3)/y) assert floor(ceiling(-floor(x**Rational(7, 2)/y))) == -floor(x**Rational(7, 2)/y) assert -ceiling(-ceiling(floor(x)/y)) == ceiling(floor(x)/y)
def test_issue_10323(): assert ceiling(sqrt(2**30 + 1)) == 2**15 + 1
def test_sympy__functions__elementary__integers__ceiling(): from sympy.functions.elementary.integers import ceiling assert _test_args(ceiling(x))
def test_floor(): assert floor(nan) is nan assert floor(oo) is oo assert floor(-oo) is -oo assert floor(zoo) is zoo assert floor(0) == 0 assert floor(1) == 1 assert floor(-1) == -1 assert floor(E) == 2 assert floor(-E) == -3 assert floor(2*E) == 5 assert floor(-2*E) == -6 assert floor(pi) == 3 assert floor(-pi) == -4 assert floor(S.Half) == 0 assert floor(Rational(-1, 2)) == -1 assert floor(Rational(7, 3)) == 2 assert floor(Rational(-7, 3)) == -3 assert floor(-Rational(7, 3)) == -3 assert floor(Float(17.0)) == 17 assert floor(-Float(17.0)) == -17 assert floor(Float(7.69)) == 7 assert floor(-Float(7.69)) == -8 assert floor(I) == I assert floor(-I) == -I e = floor(i) assert e.func is floor and e.args[0] == i assert floor(oo*I) == oo*I assert floor(-oo*I) == -oo*I assert floor(exp(I*pi/4)*oo) == exp(I*pi/4)*oo assert floor(2*I) == 2*I assert floor(-2*I) == -2*I assert floor(I/2) == 0 assert floor(-I/2) == -I assert floor(E + 17) == 19 assert floor(pi + 2) == 5 assert floor(E + pi) == 5 assert floor(I + pi) == 3 + I assert floor(floor(pi)) == 3 assert floor(floor(y)) == floor(y) assert floor(floor(x)) == floor(x) assert unchanged(floor, x) assert unchanged(floor, 2*x) assert unchanged(floor, k*x) assert floor(k) == k assert floor(2*k) == 2*k assert floor(k*n) == k*n assert unchanged(floor, k/2) assert unchanged(floor, x + y) assert floor(x + 3) == floor(x) + 3 assert floor(x + k) == floor(x) + k assert floor(y + 3) == floor(y) + 3 assert floor(y + k) == floor(y) + k assert floor(3 + I*y + pi) == 6 + floor(y)*I assert floor(k + n) == k + n assert unchanged(floor, x*I) assert floor(k*I) == k*I assert floor(Rational(23, 10) - E*I) == 2 - 3*I assert floor(sin(1)) == 0 assert floor(sin(-1)) == -1 assert floor(exp(2)) == 7 assert floor(log(8)/log(2)) != 2 assert int(floor(log(8)/log(2)).evalf(chop=True)) == 3 assert floor(factorial(50)/exp(1)) == \ 11188719610782480504630258070757734324011354208865721592720336800 assert (floor(y) < y) == False assert (floor(y) <= y) == True assert (floor(y) > y) == False assert (floor(y) >= y) == False assert (floor(x) <= x).is_Relational # x could be non-real assert (floor(x) > x).is_Relational assert (floor(x) <= y).is_Relational # arg is not same as rhs assert (floor(x) > y).is_Relational assert (floor(y) <= oo) == True assert (floor(y) < oo) == True assert (floor(y) >= -oo) == True assert (floor(y) > -oo) == True assert floor(y).rewrite(frac) == y - frac(y) assert floor(y).rewrite(ceiling) == -ceiling(-y) assert floor(y).rewrite(frac).subs(y, -pi) == floor(-pi) assert floor(y).rewrite(frac).subs(y, E) == floor(E) assert floor(y).rewrite(ceiling).subs(y, E) == -ceiling(-E) assert floor(y).rewrite(ceiling).subs(y, -pi) == -ceiling(pi) assert Eq(floor(y), y - frac(y)) assert Eq(floor(y), -ceiling(-y)) neg = Symbol('neg', negative=True) nn = Symbol('nn', nonnegative=True) pos = Symbol('pos', positive=True) np = Symbol('np', nonpositive=True) assert (floor(neg) < 0) == True assert (floor(neg) <= 0) == True assert (floor(neg) > 0) == False assert (floor(neg) >= 0) == False assert (floor(neg) <= -1) == True assert (floor(neg) >= -3) == (neg >= -3) assert (floor(neg) < 5) == (neg < 5) assert (floor(nn) < 0) == False assert (floor(nn) >= 0) == True assert (floor(pos) < 0) == False assert (floor(pos) <= 0) == (pos < 1) assert (floor(pos) > 0) == (pos >= 1) assert (floor(pos) >= 0) == True assert (floor(pos) >= 3) == (pos >= 3) assert (floor(np) <= 0) == True assert (floor(np) > 0) == False assert floor(neg).is_negative == True assert floor(neg).is_nonnegative == False assert floor(nn).is_negative == False assert floor(nn).is_nonnegative == True assert floor(pos).is_negative == False assert floor(pos).is_nonnegative == True assert floor(np).is_negative is None assert floor(np).is_nonnegative is None assert (floor(7, evaluate=False) >= 7) == True assert (floor(7, evaluate=False) > 7) == False assert (floor(7, evaluate=False) <= 7) == True assert (floor(7, evaluate=False) < 7) == False assert (floor(7, evaluate=False) >= 6) == True assert (floor(7, evaluate=False) > 6) == True assert (floor(7, evaluate=False) <= 6) == False assert (floor(7, evaluate=False) < 6) == False assert (floor(7, evaluate=False) >= 8) == False assert (floor(7, evaluate=False) > 8) == False assert (floor(7, evaluate=False) <= 8) == True assert (floor(7, evaluate=False) < 8) == True assert (floor(x) <= 5.5) == Le(floor(x), 5.5, evaluate=False) assert (floor(x) >= -3.2) == Ge(floor(x), -3.2, evaluate=False) assert (floor(x) < 2.9) == Lt(floor(x), 2.9, evaluate=False) assert (floor(x) > -1.7) == Gt(floor(x), -1.7, evaluate=False) assert (floor(y) <= 5.5) == (y < 6) assert (floor(y) >= -3.2) == (y >= -3) assert (floor(y) < 2.9) == (y < 3) assert (floor(y) > -1.7) == (y >= -1) assert (floor(y) <= n) == (y < n + 1) assert (floor(y) >= n) == (y >= n) assert (floor(y) < n) == (y < n) assert (floor(y) > n) == (y >= n + 1)
def test_frac(): assert isinstance(frac(x), frac) assert frac(oo) == AccumBounds(0, 1) assert frac(-oo) == AccumBounds(0, 1) assert frac(zoo) is nan assert frac(n) == 0 assert frac(nan) is nan assert frac(Rational(4, 3)) == Rational(1, 3) assert frac(-Rational(4, 3)) == Rational(2, 3) assert frac(Rational(-4, 3)) == Rational(2, 3) r = Symbol('r', real=True) assert frac(I*r) == I*frac(r) assert frac(1 + I*r) == I*frac(r) assert frac(0.5 + I*r) == 0.5 + I*frac(r) assert frac(n + I*r) == I*frac(r) assert frac(n + I*k) == 0 assert unchanged(frac, x + I*x) assert frac(x + I*n) == frac(x) assert frac(x).rewrite(floor) == x - floor(x) assert frac(x).rewrite(ceiling) == x + ceiling(-x) assert frac(y).rewrite(floor).subs(y, pi) == frac(pi) assert frac(y).rewrite(floor).subs(y, -E) == frac(-E) assert frac(y).rewrite(ceiling).subs(y, -pi) == frac(-pi) assert frac(y).rewrite(ceiling).subs(y, E) == frac(E) assert Eq(frac(y), y - floor(y)) assert Eq(frac(y), y + ceiling(-y)) r = Symbol('r', real=True) p_i = Symbol('p_i', integer=True, positive=True) n_i = Symbol('p_i', integer=True, negative=True) np_i = Symbol('np_i', integer=True, nonpositive=True) nn_i = Symbol('nn_i', integer=True, nonnegative=True) p_r = Symbol('p_r', positive=True) n_r = Symbol('n_r', negative=True) np_r = Symbol('np_r', real=True, nonpositive=True) nn_r = Symbol('nn_r', real=True, nonnegative=True) # Real frac argument, integer rhs assert frac(r) <= p_i assert not frac(r) <= n_i assert (frac(r) <= np_i).has(Le) assert (frac(r) <= nn_i).has(Le) assert frac(r) < p_i assert not frac(r) < n_i assert not frac(r) < np_i assert (frac(r) < nn_i).has(Lt) assert not frac(r) >= p_i assert frac(r) >= n_i assert frac(r) >= np_i assert (frac(r) >= nn_i).has(Ge) assert not frac(r) > p_i assert frac(r) > n_i assert (frac(r) > np_i).has(Gt) assert (frac(r) > nn_i).has(Gt) assert not Eq(frac(r), p_i) assert not Eq(frac(r), n_i) assert Eq(frac(r), np_i).has(Eq) assert Eq(frac(r), nn_i).has(Eq) assert Ne(frac(r), p_i) assert Ne(frac(r), n_i) assert Ne(frac(r), np_i).has(Ne) assert Ne(frac(r), nn_i).has(Ne) # Real frac argument, real rhs assert (frac(r) <= p_r).has(Le) assert not frac(r) <= n_r assert (frac(r) <= np_r).has(Le) assert (frac(r) <= nn_r).has(Le) assert (frac(r) < p_r).has(Lt) assert not frac(r) < n_r assert not frac(r) < np_r assert (frac(r) < nn_r).has(Lt) assert (frac(r) >= p_r).has(Ge) assert frac(r) >= n_r assert frac(r) >= np_r assert (frac(r) >= nn_r).has(Ge) assert (frac(r) > p_r).has(Gt) assert frac(r) > n_r assert (frac(r) > np_r).has(Gt) assert (frac(r) > nn_r).has(Gt) assert not Eq(frac(r), n_r) assert Eq(frac(r), p_r).has(Eq) assert Eq(frac(r), np_r).has(Eq) assert Eq(frac(r), nn_r).has(Eq) assert Ne(frac(r), p_r).has(Ne) assert Ne(frac(r), n_r) assert Ne(frac(r), np_r).has(Ne) assert Ne(frac(r), nn_r).has(Ne) # Real frac argument, +/- oo rhs assert frac(r) < oo assert frac(r) <= oo assert not frac(r) > oo assert not frac(r) >= oo assert not frac(r) < -oo assert not frac(r) <= -oo assert frac(r) > -oo assert frac(r) >= -oo assert frac(r) < 1 assert frac(r) <= 1 assert not frac(r) > 1 assert not frac(r) >= 1 assert not frac(r) < 0 assert (frac(r) <= 0).has(Le) assert (frac(r) > 0).has(Gt) assert frac(r) >= 0 # Some test for numbers assert frac(r) <= sqrt(2) assert (frac(r) <= sqrt(3) - sqrt(2)).has(Le) assert not frac(r) <= sqrt(2) - sqrt(3) assert not frac(r) >= sqrt(2) assert (frac(r) >= sqrt(3) - sqrt(2)).has(Ge) assert frac(r) >= sqrt(2) - sqrt(3) assert not Eq(frac(r), sqrt(2)) assert Eq(frac(r), sqrt(3) - sqrt(2)).has(Eq) assert not Eq(frac(r), sqrt(2) - sqrt(3)) assert Ne(frac(r), sqrt(2)) assert Ne(frac(r), sqrt(3) - sqrt(2)).has(Ne) assert Ne(frac(r), sqrt(2) - sqrt(3)) assert frac(p_i, evaluate=False).is_zero assert frac(p_i, evaluate=False).is_finite assert frac(p_i, evaluate=False).is_integer assert frac(p_i, evaluate=False).is_real assert frac(r).is_finite assert frac(r).is_real assert frac(r).is_zero is None assert frac(r).is_integer is None assert frac(oo).is_finite assert frac(oo).is_real
def __getitem__(self, i): ooslice = "cannot slice from the end with an infinite value" zerostep = "slice step cannot be zero" infinite = "slicing not possible on range with infinite start" # if we had to take every other element in the following # oo, ..., 6, 4, 2, 0 # we might get oo, ..., 4, 0 or oo, ..., 6, 2 ambiguous = "cannot unambiguously re-stride from the end " + \ "with an infinite value" if isinstance(i, slice): if self.size.is_finite: # validates, too if self.start == self.stop: return Range(0) start, stop, step = i.indices(self.size) n = ceiling((stop - start) / step) if n <= 0: return Range(0) canonical_stop = start + n * step end = canonical_stop - step ss = step * self.step return Range(self[start], self[end] + ss, ss) else: # infinite Range start = i.start stop = i.stop if i.step == 0: raise ValueError(zerostep) step = i.step or 1 ss = step * self.step #--------------------- # handle infinite Range # i.e. Range(-oo, oo) or Range(oo, -oo, -1) # -------------------- if self.start.is_infinite and self.stop.is_infinite: raise ValueError(infinite) #--------------------- # handle infinite on right # e.g. Range(0, oo) or Range(0, -oo, -1) # -------------------- if self.stop.is_infinite: # start and stop are not interdependent -- # they only depend on step --so we use the # equivalent reversed values return self.reversed[ stop if stop is None else -stop + 1:start if start is None else -start:step].reversed #--------------------- # handle infinite on the left # e.g. Range(oo, 0, -1) or Range(-oo, 0) # -------------------- # consider combinations of # start/stop {== None, < 0, == 0, > 0} and # step {< 0, > 0} if start is None: if stop is None: if step < 0: return Range(self[-1], self.start, ss) elif step > 1: raise ValueError(ambiguous) else: # == 1 return self elif stop < 0: if step < 0: return Range(self[-1], self[stop], ss) else: # > 0 return Range(self.start, self[stop], ss) elif stop == 0: if step > 0: return Range(0) else: # < 0 raise ValueError(ooslice) elif stop == 1: if step > 0: raise ValueError(ooslice) # infinite singleton else: # < 0 raise ValueError(ooslice) else: # > 1 raise ValueError(ooslice) elif start < 0: if stop is None: if step < 0: return Range(self[start], self.start, ss) else: # > 0 return Range(self[start], self.stop, ss) elif stop < 0: return Range(self[start], self[stop], ss) elif stop == 0: if step < 0: raise ValueError(ooslice) else: # > 0 return Range(0) elif stop > 0: raise ValueError(ooslice) elif start == 0: if stop is None: if step < 0: raise ValueError(ooslice) # infinite singleton elif step > 1: raise ValueError(ambiguous) else: # == 1 return self elif stop < 0: if step > 1: raise ValueError(ambiguous) elif step == 1: return Range(self.start, self[stop], ss) else: # < 0 return Range(0) else: # >= 0 raise ValueError(ooslice) elif start > 0: raise ValueError(ooslice) else: if self.start == self.stop: raise IndexError('Range index out of range') if not (all(i.is_integer or i.is_infinite for i in self.args) and ( (self.stop - self.start) / self.step).is_extended_positive): raise ValueError('Invalid method for symbolic Range') if i == 0: if self.start.is_infinite: raise ValueError(ooslice) return self.start if i == -1: if self.stop.is_infinite: raise ValueError(ooslice) return self.stop - self.step n = self.size # must be known for any other index rv = (self.stop if i < 0 else self.start) + i * self.step if rv.is_infinite: raise ValueError(ooslice) val = (rv - self.start) / self.step rel = fuzzy_or([ val.is_infinite, fuzzy_and([val.is_nonnegative, (n - val).is_nonnegative]) ]) if rel: return rv if rel is None: raise ValueError('Invalid method for symbolic Range') raise IndexError("Range index out of range")
def _intersect(self, other): if other.is_Interval: s = FiniteSet(range(ceiling(other.left), floor(other.right) + 1)) return s.intersect(other) # take out endpoints if open interval return None
def _real_to_rational(expr, tolerance=None, rational_conversion='base10'): """ Replace all reals in expr with rationals. >>> from sympy import Rational >>> from sympy.simplify.simplify import _real_to_rational >>> from sympy.abc import x >>> _real_to_rational(.76 + .1*x**.5) sqrt(x)/10 + 19/25 If rational_conversion='base10', this uses the base-10 string. If rational_conversion='exact', the exact, base-2 representation is used. >>> _real_to_rational(0.333333333333333, rational_conversion='exact') 6004799503160655/18014398509481984 >>> _real_to_rational(0.333333333333333) 1/3 """ expr = _sympify(expr) inf = Float('inf') p = expr reps = {} reduce_num = None if tolerance is not None and tolerance < 1: reduce_num = ceiling(1/tolerance) for fl in p.atoms(Float): key = fl if reduce_num is not None: r = Rational(fl).limit_denominator(reduce_num) elif (tolerance is not None and tolerance >= 1 and fl.is_Integer is False): r = Rational(tolerance*round(fl/tolerance) ).limit_denominator(int(tolerance)) else: if rational_conversion == 'exact': r = Rational(fl) reps[key] = r continue elif rational_conversion != 'base10': raise ValueError("rational_conversion must be 'base10' or 'exact'") r = nsimplify(fl, rational=False) # e.g. log(3).n() -> log(3) instead of a Rational if fl and not r: r = Rational(fl) elif not r.is_Rational: if fl == inf or fl == -inf: r = S.ComplexInfinity elif fl < 0: fl = -fl d = Pow(10, int((mpmath.log(fl)/mpmath.log(10)))) r = -Rational(str(fl/d))*d elif fl > 0: d = Pow(10, int((mpmath.log(fl)/mpmath.log(10)))) r = Rational(str(fl/d))*d else: r = Integer(0) reps[key] = r return p.subs(reps, simultaneous=True)
def rsolve_hypergeometric(f, x, P, Q, k, m): """Solves RE of hypergeometric type. Attempts to solve RE of the form Q(k)*a(k + m) - P(k)*a(k) Transformations that preserve Hypergeometric type: a. x**n*f(x): b(k + m) = R(k - n)*b(k) b. f(A*x): b(k + m) = A**m*R(k)*b(k) c. f(x**n): b(k + n*m) = R(k/n)*b(k) d. f(x**(1/m)): b(k + 1) = R(k*m)*b(k) e. f'(x): b(k + m) = ((k + m + 1)/(k + 1))*R(k + 1)*b(k) Some of these transformations have been used to solve the RE. Returns ======= formula : Expr ind : Expr Independent terms. order : int Examples ======== >>> from sympy import exp, ln, S >>> from sympy.series.formal import rsolve_hypergeometric as rh >>> from sympy.abc import x, k >>> rh(exp(x), x, -S.One, (k + 1), k, 1) (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1) >>> rh(ln(1 + x), x, k**2, k*(k + 1), k, 1) (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1), Eq(Mod(k, 1), 0)), (0, True)), x, 2) References ========== .. [1] Formal Power Series - Dominik Gruntz, Wolfram Koepf .. [2] Power Series in Computer Algebra - Wolfram Koepf """ result = _rsolve_hypergeometric(f, x, P, Q, k, m) if result is None: return None sol_list, ind, mp = result sol_dict = defaultdict(lambda: S.Zero) for res, cond in sol_list: j, mk = cond.as_coeff_Add() c = mk.coeff(k) if j.is_integer is False: res *= x**frac(j) j = floor(j) res = res.subs(k, (k - j) / c) cond = Eq(k % c, j % c) sol_dict[cond] += res # Group together formula for same conditions sol = [] for cond, res in sol_dict.items(): sol.append((res, cond)) sol.append((S.Zero, True)) sol = Piecewise(*sol) if mp is -oo: s = S.Zero elif mp.is_integer is False: s = ceiling(mp) else: s = mp + 1 # save all the terms of # form 1/x**k in ind if s < 0: ind += sum(sequence(sol * x**k, (k, s, -1))) s = S.Zero return (sol, ind, s)
def __new__(cls, *args): from sympy.functions.elementary.integers import ceiling if len(args) == 1: if isinstance(args[0], range): raise TypeError('use sympify(%s) to convert range to Range' % args[0]) # expand range slc = slice(*args) if slc.step == 0: raise ValueError("step cannot be 0") start, stop, step = slc.start or 0, slc.stop, slc.step or 1 try: ok = [] for w in (start, stop, step): w = sympify(w) if w in [S.NegativeInfinity, S.Infinity ] or (w.has(Symbol) and w.is_integer != False): ok.append(w) elif not w.is_Integer: raise ValueError else: ok.append(w) except ValueError: raise ValueError( filldedent(''' Finite arguments to Range must be integers; `imageset` can define other cases, e.g. use `imageset(i, i/10, Range(3))` to give [0, 1/10, 1/5].''')) start, stop, step = ok null = False if any(i.has(Symbol) for i in (start, stop, step)): if start == stop: null = True else: end = stop elif start.is_infinite: span = step * (stop - start) if span is S.NaN or span <= 0: null = True elif step.is_Integer and stop.is_infinite and abs(step) != 1: raise ValueError( filldedent(''' Step size must be %s in this case.''' % (1 if step > 0 else -1))) else: end = stop else: oostep = step.is_infinite if oostep: step = S.One if step > 0 else S.NegativeOne n = ceiling((stop - start) / step) if n <= 0: null = True elif oostep: end = start + 1 step = S.One # make it a canonical single step else: end = start + n * step if null: start = end = S.Zero step = S.One return Basic.__new__(cls, start, end, step)
def test_ceiling(): assert limit(ceiling(x), x, -2, "+") == -1 assert limit(ceiling(x), x, -2, "-") == -2 assert limit(ceiling(x), x, -1, "+") == 0 assert limit(ceiling(x), x, -1, "-") == -1 assert limit(ceiling(x), x, 0, "+") == 1 assert limit(ceiling(x), x, 0, "-") == 0 assert limit(ceiling(x), x, 1, "+") == 2 assert limit(ceiling(x), x, 1, "-") == 1 assert limit(ceiling(x), x, 2, "+") == 3 assert limit(ceiling(x), x, 2, "-") == 2 assert limit(ceiling(x), x, 248, "+") == 249 assert limit(ceiling(x), x, 248, "-") == 248 # https://github.com/sympy/sympy/issues/14478 assert limit(x*ceiling(3/x)/2, x, 0, '+') == Rational(3, 2) assert limit(ceiling(x + 1/2) - ceiling(x), x, oo) == AccumBounds(-S.Half, S(3)/2)
def _intersect(self, other): if other.is_Interval and other.measure < oo: s = Range(ceiling(other.left), floor(other.right) + 1) return s.intersect(other) # take out endpoints if open interval return None
def _intersect(self, other): from sympy.functions.elementary.integers import ceiling, floor from sympy.functions.elementary.complexes import sign if other is S.Naturals: return self._intersect(Interval(1, S.Infinity)) if other is S.Integers: return self if other.is_Interval: if not all(i.is_number for i in other.args[:2]): return # In case of null Range, return an EmptySet. if self.size == 0: return S.EmptySet # trim down to self's size, and represent # as a Range with step 1. start = ceiling(max(other.inf, self.inf)) if start not in other: start += 1 end = floor(min(other.sup, self.sup)) if end not in other: end -= 1 return self.intersect(Range(start, end + 1)) if isinstance(other, Range): from sympy.solvers.diophantine import diop_linear from sympy.core.numbers import ilcm # non-overlap quick exits if not other: return S.EmptySet if not self: return S.EmptySet if other.sup < self.inf: return S.EmptySet if other.inf > self.sup: return S.EmptySet # work with finite end at the start r1 = self if r1.start.is_infinite: r1 = r1.reversed r2 = other if r2.start.is_infinite: r2 = r2.reversed # this equation represents the values of the Range; # it's a linear equation eq = lambda r, i: r.start + i * r.step # we want to know when the two equations might # have integer solutions so we use the diophantine # solver a, b = diop_linear(eq(r1, Dummy()) - eq(r2, Dummy())) # check for no solution no_solution = a is None and b is None if no_solution: return S.EmptySet # there is a solution # ------------------- # find the coincident point, c a0 = a.as_coeff_Add()[0] c = eq(r1, a0) # find the first point, if possible, in each range # since c may not be that point def _first_finite_point(r1, c): if c == r1.start: return c # st is the signed step we need to take to # get from c to r1.start st = sign(r1.start - c) * step # use Range to calculate the first point: # we want to get as close as possible to # r1.start; the Range will not be null since # it will at least contain c s1 = Range(c, r1.start + st, st)[-1] if s1 == r1.start: pass else: # if we didn't hit r1.start then, if the # sign of st didn't match the sign of r1.step # we are off by one and s1 is not in r1 if sign(r1.step) != sign(st): s1 -= st if s1 not in r1: return return s1 # calculate the step size of the new Range step = abs(ilcm(r1.step, r2.step)) s1 = _first_finite_point(r1, c) if s1 is None: return S.EmptySet s2 = _first_finite_point(r2, c) if s2 is None: return S.EmptySet # replace the corresponding start or stop in # the original Ranges with these points; the # result must have at least one point since # we know that s1 and s2 are in the Ranges def _updated_range(r, first): st = sign(r.step) * step if r.start.is_finite: rv = Range(first, r.stop, st) else: rv = Range(r.start, first + st, st) return rv r1 = _updated_range(self, s1) r2 = _updated_range(other, s2) # work with them both in the increasing direction if sign(r1.step) < 0: r1 = r1.reversed if sign(r2.step) < 0: r2 = r2.reversed # return clipped Range with positive step; it # can't be empty at this point start = max(r1.start, r2.start) stop = min(r1.stop, r2.stop) return Range(start, stop, step) else: return
def test_issue_18421(): assert floor(float(0)) is S.Zero assert ceiling(float(0)) is S.Zero
def __getitem__(self, i): from sympy.functions.elementary.integers import ceiling ooslice = "cannot slice from the end with an infinite value" zerostep = "slice step cannot be zero" # if we had to take every other element in the following # oo, ..., 6, 4, 2, 0 # we might get oo, ..., 4, 0 or oo, ..., 6, 2 ambiguous = "cannot unambiguously re-stride from the end " + \ "with an infinite value" if isinstance(i, slice): if self.size.is_finite: start, stop, step = i.indices(self.size) n = ceiling((stop - start) / step) if n <= 0: return Range(0) canonical_stop = start + n * step end = canonical_stop - step ss = step * self.step return Range(self[start], self[end] + ss, ss) else: # infinite Range start = i.start stop = i.stop if i.step == 0: raise ValueError(zerostep) step = i.step or 1 ss = step * self.step #--------------------- # handle infinite on right # e.g. Range(0, oo) or Range(0, -oo, -1) # -------------------- if self.stop.is_infinite: # start and stop are not interdependent -- # they only depend on step --so we use the # equivalent reversed values return self.reversed[ stop if stop is None else -stop + 1:start if start is None else -start:step].reversed #--------------------- # handle infinite on the left # e.g. Range(oo, 0, -1) or Range(-oo, 0) # -------------------- # consider combinations of # start/stop {== None, < 0, == 0, > 0} and # step {< 0, > 0} if start is None: if stop is None: if step < 0: return Range(self[-1], self.start, ss) elif step > 1: raise ValueError(ambiguous) else: # == 1 return self elif stop < 0: if step < 0: return Range(self[-1], self[stop], ss) else: # > 0 return Range(self.start, self[stop], ss) elif stop == 0: if step > 0: return Range(0) else: # < 0 raise ValueError(ooslice) elif stop == 1: if step > 0: raise ValueError(ooslice) # infinite singleton else: # < 0 raise ValueError(ooslice) else: # > 1 raise ValueError(ooslice) elif start < 0: if stop is None: if step < 0: return Range(self[start], self.start, ss) else: # > 0 return Range(self[start], self.stop, ss) elif stop < 0: return Range(self[start], self[stop], ss) elif stop == 0: if step < 0: raise ValueError(ooslice) else: # > 0 return Range(0) elif stop > 0: raise ValueError(ooslice) elif start == 0: if stop is None: if step < 0: raise ValueError(ooslice) # infinite singleton elif step > 1: raise ValueError(ambiguous) else: # == 1 return self elif stop < 0: if step > 1: raise ValueError(ambiguous) elif step == 1: return Range(self.start, self[stop], ss) else: # < 0 return Range(0) else: # >= 0 raise ValueError(ooslice) elif start > 0: raise ValueError(ooslice) else: if not self: raise IndexError('Range index out of range') if i == 0: return self.start if i == -1 or i is S.Infinity: return self.stop - self.step rv = (self.stop if i < 0 else self.start) + i * self.step if rv.is_infinite: raise ValueError(ooslice) if rv < self.inf or rv > self.sup: raise IndexError("Range index out of range") return rv
def test_issue_18689(): assert floor(floor(floor(x)) + 3) == floor(x) + 3 assert ceiling(ceiling(ceiling(x)) + 1) == ceiling(x) + 1 assert ceiling(ceiling(floor(x)) + 3) == floor(x) + 3
def test_issue_11207(): assert floor(floor(x)) == floor(x) assert floor(ceiling(x)) == ceiling(x) assert ceiling(floor(x)) == floor(x) assert ceiling(ceiling(x)) == ceiling(x)
def test_DiscreteMarkovChain(): # pass only the name X = DiscreteMarkovChain("X") assert isinstance(X.state_space, Range) assert X.index_set == S.Naturals0 assert isinstance(X.transition_probabilities, MatrixSymbol) t = symbols('t', positive=True, integer=True) assert isinstance(X[t], RandomIndexedSymbol) assert E(X[0]) == Expectation(X[0]) raises(TypeError, lambda: DiscreteMarkovChain(1)) raises(NotImplementedError, lambda: X(t)) raises(NotImplementedError, lambda: X.communication_classes()) raises(NotImplementedError, lambda: X.canonical_form()) raises(NotImplementedError, lambda: X.decompose()) nz = Symbol('n', integer=True) TZ = MatrixSymbol('M', nz, nz) SZ = Range(nz) YZ = DiscreteMarkovChain('Y', SZ, TZ) assert P(Eq(YZ[2], 1), Eq(YZ[1], 0)) == TZ[0, 1] raises(ValueError, lambda: sample_stochastic_process(t)) raises(ValueError, lambda: next(sample_stochastic_process(X))) # pass name and state_space # any hashable object should be a valid state # states should be valid as a tuple/set/list/Tuple/Range sym, rainy, cloudy, sunny = symbols('a Rainy Cloudy Sunny', real=True) state_spaces = [(1, 2, 3), [Str('Hello'), sym, DiscreteMarkovChain], Tuple(S(1), exp(sym), Str('World'), sympify=False), Range(-1, 5, 2), [rainy, cloudy, sunny]] chains = [ DiscreteMarkovChain("Y", state_space) for state_space in state_spaces ] for i, Y in enumerate(chains): assert isinstance(Y.transition_probabilities, MatrixSymbol) assert Y.state_space == state_spaces[i] or Y.state_space == FiniteSet( *state_spaces[i]) assert Y.number_of_states == 3 with ignore_warnings( UserWarning): # TODO: Restore tests once warnings are removed assert P(Eq(Y[2], 1), Eq(Y[0], 2), evaluate=False) == Probability(Eq(Y[2], 1), Eq(Y[0], 2)) assert E(Y[0]) == Expectation(Y[0]) raises(ValueError, lambda: next(sample_stochastic_process(Y))) raises(TypeError, lambda: DiscreteMarkovChain("Y", dict((1, 1)))) Y = DiscreteMarkovChain("Y", Range(1, t, 2)) assert Y.number_of_states == ceiling((t - 1) / 2) # pass name and transition_probabilities chains = [ DiscreteMarkovChain("Y", trans_probs=Matrix([[]])), DiscreteMarkovChain("Y", trans_probs=Matrix([[0, 1], [1, 0]])), DiscreteMarkovChain("Y", trans_probs=Matrix([[pi, 1 - pi], [sym, 1 - sym]])) ] for Z in chains: assert Z.number_of_states == Z.transition_probabilities.shape[0] assert isinstance(Z.transition_probabilities, ImmutableMatrix) # pass name, state_space and transition_probabilities T = Matrix([[0.5, 0.2, 0.3], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5]]) TS = MatrixSymbol('T', 3, 3) Y = DiscreteMarkovChain("Y", [0, 1, 2], T) YS = DiscreteMarkovChain("Y", ['One', 'Two', 3], TS) assert Y.joint_distribution(1, Y[2], 3) == JointDistribution(Y[1], Y[2], Y[3]) raises(ValueError, lambda: Y.joint_distribution(Y[1].symbol, Y[2].symbol)) assert P(Eq(Y[3], 2), Eq(Y[1], 1)).round(2) == Float(0.36, 2) assert (P(Eq(YS[3], 2), Eq(YS[1], 1)) - (TS[0, 2] * TS[1, 0] + TS[1, 1] * TS[1, 2] + TS[1, 2] * TS[2, 2])).simplify() == 0 assert P(Eq(YS[1], 1), Eq(YS[2], 2)) == Probability(Eq(YS[1], 1)) assert P(Eq(YS[3], 3), Eq( YS[1], 1)) == TS[0, 2] * TS[1, 0] + TS[1, 1] * TS[1, 2] + TS[1, 2] * TS[2, 2] TO = Matrix([[0.25, 0.75, 0], [0, 0.25, 0.75], [0.75, 0, 0.25]]) assert P(Eq(Y[3], 2), Eq(Y[1], 1) & TransitionMatrixOf(Y, TO)).round(3) == Float( 0.375, 3) with ignore_warnings( UserWarning): ### TODO: Restore tests once warnings are removed assert E(Y[3], evaluate=False) == Expectation(Y[3]) assert E(Y[3], Eq(Y[2], 1)).round(2) == Float(1.1, 3) TSO = MatrixSymbol('T', 4, 4) raises( ValueError, lambda: str(P(Eq(YS[3], 2), Eq(YS[1], 1) & TransitionMatrixOf(YS, TSO)))) raises(TypeError, lambda: DiscreteMarkovChain("Z", [0, 1, 2], symbols('M'))) raises( ValueError, lambda: DiscreteMarkovChain("Z", [0, 1, 2], MatrixSymbol('T', 3, 4))) raises(ValueError, lambda: E(Y[3], Eq(Y[2], 6))) raises(ValueError, lambda: E(Y[2], Eq(Y[3], 1))) # extended tests for probability queries TO1 = Matrix([[Rational(1, 4), Rational(3, 4), 0], [Rational(1, 3), Rational(1, 3), Rational(1, 3)], [0, Rational(1, 4), Rational(3, 4)]]) assert P( And(Eq(Y[2], 1), Eq(Y[1], 1), Eq(Y[0], 0)), Eq(Probability(Eq(Y[0], 0)), Rational(1, 4)) & TransitionMatrixOf(Y, TO1)) == Rational(1, 16) assert P(And(Eq(Y[2], 1), Eq(Y[1], 1), Eq(Y[0], 0)), TransitionMatrixOf(Y, TO1)) == \ Probability(Eq(Y[0], 0))/4 assert P( Lt(X[1], 2) & Gt(X[1], 0), Eq(X[0], 2) & StochasticStateSpaceOf(X, [0, 1, 2]) & TransitionMatrixOf(X, TO1)) == Rational(1, 4) assert P( Lt(X[1], 2) & Gt(X[1], 0), Eq(X[0], 2) & StochasticStateSpaceOf(X, [None, 'None', 1]) & TransitionMatrixOf(X, TO1)) == Rational(1, 4) assert P( Ne(X[1], 2) & Ne(X[1], 1), Eq(X[0], 2) & StochasticStateSpaceOf(X, [0, 1, 2]) & TransitionMatrixOf(X, TO1)) is S.Zero assert P( Ne(X[1], 2) & Ne(X[1], 1), Eq(X[0], 2) & StochasticStateSpaceOf(X, [None, 'None', 1]) & TransitionMatrixOf(X, TO1)) is S.Zero assert P(And(Eq(Y[2], 1), Eq(Y[1], 1), Eq(Y[0], 0)), Eq(Y[1], 1)) == 0.1 * Probability(Eq(Y[0], 0)) # testing properties of Markov chain TO2 = Matrix([[S.One, 0, 0], [Rational(1, 3), Rational(1, 3), Rational(1, 3)], [0, Rational(1, 4), Rational(3, 4)]]) TO3 = Matrix([[Rational(1, 4), Rational(3, 4), 0], [Rational(1, 3), Rational(1, 3), Rational(1, 3)], [0, Rational(1, 4), Rational(3, 4)]]) Y2 = DiscreteMarkovChain('Y', trans_probs=TO2) Y3 = DiscreteMarkovChain('Y', trans_probs=TO3) assert Y3.fundamental_matrix() == ImmutableMatrix( [[176, 81, -132], [36, 141, -52], [-44, -39, 208]]) / 125 assert Y2.is_absorbing_chain() == True assert Y3.is_absorbing_chain() == False assert Y2.canonical_form() == ([0, 1, 2], TO2) assert Y3.canonical_form() == ([0, 1, 2], TO3) assert Y2.decompose() == ([0, 1, 2], TO2[0:1, 0:1], TO2[1:3, 0:1], TO2[1:3, 1:3]) assert Y3.decompose() == ([0, 1, 2], TO3, Matrix(0, 3, []), Matrix(0, 0, [])) TO4 = Matrix([[Rational(1, 5), Rational(2, 5), Rational(2, 5)], [Rational(1, 10), S.Half, Rational(2, 5)], [Rational(3, 5), Rational(3, 10), Rational(1, 10)]]) Y4 = DiscreteMarkovChain('Y', trans_probs=TO4) w = ImmutableMatrix([[Rational(11, 39), Rational(16, 39), Rational(4, 13)]]) assert Y4.limiting_distribution == w assert Y4.is_regular() == True assert Y4.is_ergodic() == True TS1 = MatrixSymbol('T', 3, 3) Y5 = DiscreteMarkovChain('Y', trans_probs=TS1) assert Y5.limiting_distribution(w, TO4).doit() == True assert Y5.stationary_distribution(condition_set=True).subs( TS1, TO4).contains(w).doit() == S.true TO6 = Matrix([[S.One, 0, 0, 0, 0], [S.Half, 0, S.Half, 0, 0], [0, S.Half, 0, S.Half, 0], [0, 0, S.Half, 0, S.Half], [0, 0, 0, 0, 1]]) Y6 = DiscreteMarkovChain('Y', trans_probs=TO6) assert Y6.fundamental_matrix() == ImmutableMatrix( [[Rational(3, 2), S.One, S.Half], [S.One, S(2), S.One], [S.Half, S.One, Rational(3, 2)]]) assert Y6.absorbing_probabilities() == ImmutableMatrix( [[Rational(3, 4), Rational(1, 4)], [S.Half, S.Half], [Rational(1, 4), Rational(3, 4)]]) TO7 = Matrix([[Rational(1, 2), Rational(1, 4), Rational(1, 4)], [Rational(1, 2), 0, Rational(1, 2)], [Rational(1, 4), Rational(1, 4), Rational(1, 2)]]) Y7 = DiscreteMarkovChain('Y', trans_probs=TO7) assert Y7.is_absorbing_chain() == False assert Y7.fundamental_matrix() == ImmutableMatrix( [[Rational(86, 75), Rational(1, 25), Rational(-14, 75)], [Rational(2, 25), Rational(21, 25), Rational(2, 25)], [Rational(-14, 75), Rational(1, 25), Rational(86, 75)]]) # test for zero-sized matrix functionality X = DiscreteMarkovChain('X', trans_probs=Matrix([[]])) assert X.number_of_states == 0 assert X.stationary_distribution() == Matrix([[]]) assert X.communication_classes() == [] assert X.canonical_form() == ([], Matrix([[]])) assert X.decompose() == ([], Matrix([[]]), Matrix([[]]), Matrix([[]])) assert X.is_regular() == False assert X.is_ergodic() == False # test communication_class # see https://drive.google.com/drive/folders/1HbxLlwwn2b3U8Lj7eb_ASIUb5vYaNIjg?usp=sharing # tutorial 2.pdf TO7 = Matrix([[0, 5, 5, 0, 0], [0, 0, 0, 10, 0], [5, 0, 5, 0, 0], [0, 10, 0, 0, 0], [0, 3, 0, 3, 4]]) / 10 Y7 = DiscreteMarkovChain('Y', trans_probs=TO7) tuples = Y7.communication_classes() classes, recurrence, periods = list(zip(*tuples)) assert classes == ([1, 3], [0, 2], [4]) assert recurrence == (True, False, False) assert periods == (2, 1, 1) TO8 = Matrix([[0, 0, 0, 10, 0, 0], [5, 0, 5, 0, 0, 0], [0, 4, 0, 0, 0, 6], [10, 0, 0, 0, 0, 0], [0, 10, 0, 0, 0, 0], [0, 0, 0, 5, 5, 0] ]) / 10 Y8 = DiscreteMarkovChain('Y', trans_probs=TO8) tuples = Y8.communication_classes() classes, recurrence, periods = list(zip(*tuples)) assert classes == ([0, 3], [1, 2, 5, 4]) assert recurrence == (True, False) assert periods == (2, 2) TO9 = Matrix( [[2, 0, 0, 3, 0, 0, 3, 2, 0, 0], [0, 10, 0, 0, 0, 0, 0, 0, 0, 0], [0, 2, 2, 0, 0, 0, 0, 0, 3, 3], [0, 0, 0, 3, 0, 0, 6, 1, 0, 0], [0, 0, 0, 0, 5, 5, 0, 0, 0, 0], [0, 0, 0, 0, 0, 10, 0, 0, 0, 0], [4, 0, 0, 5, 0, 0, 1, 0, 0, 0], [2, 0, 0, 4, 0, 0, 2, 2, 0, 0], [3, 0, 1, 0, 0, 0, 0, 0, 4, 2], [0, 0, 4, 0, 0, 0, 0, 0, 3, 3]]) / 10 Y9 = DiscreteMarkovChain('Y', trans_probs=TO9) tuples = Y9.communication_classes() classes, recurrence, periods = list(zip(*tuples)) assert classes == ([0, 3, 6, 7], [1], [2, 8, 9], [5], [4]) assert recurrence == (True, True, False, True, False) assert periods == (1, 1, 1, 1, 1) # test canonical form # see https://www.dartmouth.edu/~chance/teaching_aids/books_articles/probability_book/Chapter11.pdf # example 11.13 T = Matrix([[1, 0, 0, 0, 0], [S(1) / 2, 0, S(1) / 2, 0, 0], [0, S(1) / 2, 0, S(1) / 2, 0], [0, 0, S(1) / 2, 0, S(1) / 2], [0, 0, 0, 0, S(1)]]) DW = DiscreteMarkovChain('DW', [0, 1, 2, 3, 4], T) states, A, B, C = DW.decompose() assert states == [0, 4, 1, 2, 3] assert A == Matrix([[1, 0], [0, 1]]) assert B == Matrix([[S(1) / 2, 0], [0, 0], [0, S(1) / 2]]) assert C == Matrix([[0, S(1) / 2, 0], [S(1) / 2, 0, S(1) / 2], [0, S(1) / 2, 0]]) states, new_matrix = DW.canonical_form() assert states == [0, 4, 1, 2, 3] assert new_matrix == Matrix([[1, 0, 0, 0, 0], [0, 1, 0, 0, 0], [S(1) / 2, 0, 0, S(1) / 2, 0], [0, 0, S(1) / 2, 0, S(1) / 2], [0, S(1) / 2, 0, S(1) / 2, 0]]) # test regular and ergodic # https://www.dartmouth.edu/~chance/teaching_aids/books_articles/probability_book/Chapter11.pdf T = Matrix([[0, 4, 0, 0, 0], [1, 0, 3, 0, 0], [0, 2, 0, 2, 0], [0, 0, 3, 0, 1], [0, 0, 0, 4, 0]]) / 4 X = DiscreteMarkovChain('X', trans_probs=T) assert not X.is_regular() assert X.is_ergodic() T = Matrix([[0, 1], [1, 0]]) X = DiscreteMarkovChain('X', trans_probs=T) assert not X.is_regular() assert X.is_ergodic() # http://www.math.wisc.edu/~valko/courses/331/MC2.pdf T = Matrix([[2, 1, 1], [2, 0, 2], [1, 1, 2]]) / 4 X = DiscreteMarkovChain('X', trans_probs=T) assert X.is_regular() assert X.is_ergodic() # https://docs.ufpr.br/~lucambio/CE222/1S2014/Kemeny-Snell1976.pdf T = Matrix([[1, 1], [1, 1]]) / 2 X = DiscreteMarkovChain('X', trans_probs=T) assert X.is_regular() assert X.is_ergodic() # test is_absorbing_chain T = Matrix([[0, 1, 0], [1, 0, 0], [0, 0, 1]]) X = DiscreteMarkovChain('X', trans_probs=T) assert not X.is_absorbing_chain() # https://en.wikipedia.org/wiki/Absorbing_Markov_chain T = Matrix([[1, 1, 0, 0], [0, 1, 1, 0], [1, 0, 0, 1], [0, 0, 0, 2]]) / 2 X = DiscreteMarkovChain('X', trans_probs=T) assert X.is_absorbing_chain() T = Matrix([[2, 0, 0, 0, 0], [1, 0, 1, 0, 0], [0, 1, 0, 1, 0], [0, 0, 1, 0, 1], [0, 0, 0, 0, 2]]) / 2 X = DiscreteMarkovChain('X', trans_probs=T) assert X.is_absorbing_chain() # test custom state space Y10 = DiscreteMarkovChain('Y', [1, 2, 3], TO2) tuples = Y10.communication_classes() classes, recurrence, periods = list(zip(*tuples)) assert classes == ([1], [2, 3]) assert recurrence == (True, False) assert periods == (1, 1) assert Y10.canonical_form() == ([1, 2, 3], TO2) assert Y10.decompose() == ([1, 2, 3], TO2[0:1, 0:1], TO2[1:3, 0:1], TO2[1:3, 1:3]) # testing miscellaneous queries T = Matrix([[S.Half, Rational(1, 4), Rational(1, 4)], [Rational(1, 3), 0, Rational(2, 3)], [S.Half, S.Half, 0]]) X = DiscreteMarkovChain('X', [0, 1, 2], T) assert P( Eq(X[1], 2) & Eq(X[2], 1) & Eq(X[3], 0), Eq(P(Eq(X[1], 0)), Rational(1, 4)) & Eq(P(Eq(X[1], 1)), Rational(1, 4))) == Rational(1, 12) assert P(Eq(X[2], 1) | Eq(X[2], 2), Eq(X[1], 1)) == Rational(2, 3) assert P(Eq(X[2], 1) & Eq(X[2], 2), Eq(X[1], 1)) is S.Zero assert P(Ne(X[2], 2), Eq(X[1], 1)) == Rational(1, 3) assert E(X[1]**2, Eq(X[0], 1)) == Rational(8, 3) assert variance(X[1], Eq(X[0], 1)) == Rational(8, 9) raises(ValueError, lambda: E(X[1], Eq(X[2], 1))) raises(ValueError, lambda: DiscreteMarkovChain('X', [0, 1], T)) # testing miscellaneous queries with different state space X = DiscreteMarkovChain('X', ['A', 'B', 'C'], T) assert P( Eq(X[1], 2) & Eq(X[2], 1) & Eq(X[3], 0), Eq(P(Eq(X[1], 0)), Rational(1, 4)) & Eq(P(Eq(X[1], 1)), Rational(1, 4))) == Rational(1, 12) assert P(Eq(X[2], 1) | Eq(X[2], 2), Eq(X[1], 1)) == Rational(2, 3) assert P(Eq(X[2], 1) & Eq(X[2], 2), Eq(X[1], 1)) is S.Zero assert P(Ne(X[2], 2), Eq(X[1], 1)) == Rational(1, 3) a = X.state_space.args[0] c = X.state_space.args[2] assert (E(X[1]**2, Eq(X[0], 1)) - (a**2 / 3 + 2 * c**2 / 3)).simplify() == 0 assert (variance(X[1], Eq(X[0], 1)) - (2 * (-a / 3 + c / 3)**2 / 3 + (2 * a / 3 - 2 * c / 3)**2 / 3)).simplify() == 0 raises(ValueError, lambda: E(X[1], Eq(X[2], 1))) #testing queries with multiple RandomIndexedSymbols T = Matrix([[Rational(5, 10), Rational(3, 10), Rational(2, 10)], [Rational(2, 10), Rational(7, 10), Rational(1, 10)], [Rational(3, 10), Rational(3, 10), Rational(4, 10)]]) Y = DiscreteMarkovChain("Y", [0, 1, 2], T) assert P(Eq(Y[7], Y[5]), Eq(Y[2], 0)).round(5) == Float(0.44428, 5) assert P(Gt(Y[3], Y[1]), Eq(Y[0], 0)).round(2) == Float(0.36, 2) assert P(Le(Y[5], Y[10]), Eq(Y[4], 2)).round(6) == Float(0.583120, 6) assert Float(P(Eq(Y[10], Y[5]), Eq(Y[4], 1)), 14) == Float(1 - P(Ne(Y[10], Y[5]), Eq(Y[4], 1)), 14) assert Float(P(Gt(Y[8], Y[9]), Eq(Y[3], 2)), 14) == Float(1 - P(Le(Y[8], Y[9]), Eq(Y[3], 2)), 14) assert Float(P(Lt(Y[1], Y[4]), Eq(Y[0], 0)), 14) == Float(1 - P(Ge(Y[1], Y[4]), Eq(Y[0], 0)), 14) assert P(Eq(Y[5], Y[10]), Eq(Y[2], 1)) == P(Eq(Y[10], Y[5]), Eq(Y[2], 1)) assert P(Gt(Y[1], Y[2]), Eq(Y[0], 1)) == P(Lt(Y[2], Y[1]), Eq(Y[0], 1)) assert P(Ge(Y[7], Y[6]), Eq(Y[4], 1)) == P(Le(Y[6], Y[7]), Eq(Y[4], 1)) #test symbolic queries a, b, c, d = symbols('a b c d') T = Matrix([[Rational(1, 10), Rational(4, 10), Rational(5, 10)], [Rational(3, 10), Rational(4, 10), Rational(3, 10)], [Rational(7, 10), Rational(2, 10), Rational(1, 10)]]) Y = DiscreteMarkovChain("Y", [0, 1, 2], T) query = P(Eq(Y[a], b), Eq(Y[c], d)) assert query.subs({ a: 10, b: 2, c: 5, d: 1 }).evalf().round(4) == P(Eq(Y[10], 2), Eq(Y[5], 1)).round(4) assert query.subs({ a: 15, b: 0, c: 10, d: 1 }).evalf().round(4) == P(Eq(Y[15], 0), Eq(Y[10], 1)).round(4) query_gt = P(Gt(Y[a], b), Eq(Y[c], d)) query_le = P(Le(Y[a], b), Eq(Y[c], d)) assert query_gt.subs({ a: 5, b: 2, c: 1, d: 0 }).evalf() + query_le.subs({ a: 5, b: 2, c: 1, d: 0 }).evalf() == 1 query_ge = P(Ge(Y[a], b), Eq(Y[c], d)) query_lt = P(Lt(Y[a], b), Eq(Y[c], d)) assert query_ge.subs({ a: 4, b: 1, c: 0, d: 2 }).evalf() + query_lt.subs({ a: 4, b: 1, c: 0, d: 2 }).evalf() == 1 #test issue 20078 assert (2 * Y[1] + 3 * Y[1]).simplify() == 5 * Y[1] assert (2 * Y[1] - 3 * Y[1]).simplify() == -Y[1] assert (2 * (0.25 * Y[1])).simplify() == 0.5 * Y[1] assert ((2 * Y[1]) * (0.25 * Y[1])).simplify() == 0.5 * Y[1]**2 assert (Y[1]**2 + Y[1]**3).simplify() == (Y[1] + 1) * Y[1]**2
def _intersect(self, other): from sympy.functions.elementary.integers import ceiling, floor from sympy.functions.elementary.complexes import sign if other is S.Naturals: return self._intersect(Interval(1, S.Infinity)) if other is S.Integers: return self if other.is_Interval: if not all(i.is_number for i in other.args[:2]): return # In case of null Range, return an EmptySet. if self.size == 0: return S.EmptySet # trim down to self's size, and represent # as a Range with step 1. start = ceiling(max(other.inf, self.inf)) if start not in other: start += 1 end = floor(min(other.sup, self.sup)) if end not in other: end -= 1 return self.intersect(Range(start, end + 1)) if isinstance(other, Range): from sympy.solvers.diophantine import diop_linear from sympy.core.numbers import ilcm # non-overlap quick exits if not other: return S.EmptySet if not self: return S.EmptySet if other.sup < self.inf: return S.EmptySet if other.inf > self.sup: return S.EmptySet # work with finite end at the start r1 = self if r1.start.is_infinite: r1 = r1.reversed r2 = other if r2.start.is_infinite: r2 = r2.reversed # this equation represents the values of the Range; # it's a linear equation eq = lambda r, i: r.start + i*r.step # we want to know when the two equations might # have integer solutions so we use the diophantine # solver a, b = diop_linear(eq(r1, Dummy()) - eq(r2, Dummy())) # check for no solution no_solution = a is None and b is None if no_solution: return S.EmptySet # there is a solution # ------------------- # find the coincident point, c a0 = a.as_coeff_Add()[0] c = eq(r1, a0) # find the first point, if possible, in each range # since c may not be that point def _first_finite_point(r1, c): if c == r1.start: return c # st is the signed step we need to take to # get from c to r1.start st = sign(r1.start - c)*step # use Range to calculate the first point: # we want to get as close as possible to # r1.start; the Range will not be null since # it will at least contain c s1 = Range(c, r1.start + st, st)[-1] if s1 == r1.start: pass else: # if we didn't hit r1.start then, if the # sign of st didn't match the sign of r1.step # we are off by one and s1 is not in r1 if sign(r1.step) != sign(st): s1 -= st if s1 not in r1: return return s1 # calculate the step size of the new Range step = abs(ilcm(r1.step, r2.step)) s1 = _first_finite_point(r1, c) if s1 is None: return S.EmptySet s2 = _first_finite_point(r2, c) if s2 is None: return S.EmptySet # replace the corresponding start or stop in # the original Ranges with these points; the # result must have at least one point since # we know that s1 and s2 are in the Ranges def _updated_range(r, first): st = sign(r.step)*step if r.start.is_finite: rv = Range(first, r.stop, st) else: rv = Range(r.start, first + st, st) return rv r1 = _updated_range(self, s1) r2 = _updated_range(other, s2) # work with them both in the increasing direction if sign(r1.step) < 0: r1 = r1.reversed if sign(r2.step) < 0: r2 = r2.reversed # return clipped Range with positive step; it # can't be empty at this point start = max(r1.start, r2.start) stop = min(r1.stop, r2.stop) return Range(start, stop, step) else: return
def intersection_sets(a, b): from sympy.functions.elementary.integers import floor, ceiling if b._inf == S.NegativeInfinity and b._sup == S.Infinity: return a s = Range(ceiling(b.left), floor(b.right) + 1) return intersection_sets(s, b) # take out endpoints if open interval
def __getitem__(self, i): from sympy.functions.elementary.integers import ceiling ooslice = "cannot slice from the end with an infinite value" zerostep = "slice step cannot be zero" # if we had to take every other element in the following # oo, ..., 6, 4, 2, 0 # we might get oo, ..., 4, 0 or oo, ..., 6, 2 ambiguous = "cannot unambiguously re-stride from the end " + \ "with an infinite value" if isinstance(i, slice): if self.size.is_finite: start, stop, step = i.indices(self.size) n = ceiling((stop - start)/step) if n <= 0: return Range(0) canonical_stop = start + n*step end = canonical_stop - step ss = step*self.step return Range(self[start], self[end] + ss, ss) else: # infinite Range start = i.start stop = i.stop if i.step == 0: raise ValueError(zerostep) step = i.step or 1 ss = step*self.step #--------------------- # handle infinite on right # e.g. Range(0, oo) or Range(0, -oo, -1) # -------------------- if self.stop.is_infinite: # start and stop are not interdependent -- # they only depend on step --so we use the # equivalent reversed values return self.reversed[ stop if stop is None else -stop + 1: start if start is None else -start: step].reversed #--------------------- # handle infinite on the left # e.g. Range(oo, 0, -1) or Range(-oo, 0) # -------------------- # consider combinations of # start/stop {== None, < 0, == 0, > 0} and # step {< 0, > 0} if start is None: if stop is None: if step < 0: return Range(self[-1], self.start, ss) elif step > 1: raise ValueError(ambiguous) else: # == 1 return self elif stop < 0: if step < 0: return Range(self[-1], self[stop], ss) else: # > 0 return Range(self.start, self[stop], ss) elif stop == 0: if step > 0: return Range(0) else: # < 0 raise ValueError(ooslice) elif stop == 1: if step > 0: raise ValueError(ooslice) # infinite singleton else: # < 0 raise ValueError(ooslice) else: # > 1 raise ValueError(ooslice) elif start < 0: if stop is None: if step < 0: return Range(self[start], self.start, ss) else: # > 0 return Range(self[start], self.stop, ss) elif stop < 0: return Range(self[start], self[stop], ss) elif stop == 0: if step < 0: raise ValueError(ooslice) else: # > 0 return Range(0) elif stop > 0: raise ValueError(ooslice) elif start == 0: if stop is None: if step < 0: raise ValueError(ooslice) # infinite singleton elif step > 1: raise ValueError(ambiguous) else: # == 1 return self elif stop < 0: if step > 1: raise ValueError(ambiguous) elif step == 1: return Range(self.start, self[stop], ss) else: # < 0 return Range(0) else: # >= 0 raise ValueError(ooslice) elif start > 0: raise ValueError(ooslice) else: if not self: raise IndexError('Range index out of range') if i == 0: return self.start if i == -1 or i is S.Infinity: return self.stop - self.step rv = (self.stop if i < 0 else self.start) + i*self.step if rv.is_infinite: raise ValueError(ooslice) if rv < self.inf or rv > self.sup: raise IndexError("Range index out of range") return rv
def primerange(a, b): """ Generate a list of all prime numbers in the range [a, b). If the range exists in the default sieve, the values will be returned from there; otherwise values will be returned but will not modify the sieve. Notes ===== Some famous conjectures about the occurence of primes in a given range are [1]: - Twin primes: though often not, the following will give 2 primes an infinite number of times: primerange(6*n - 1, 6*n + 2) - Legendre's: the following always yields at least one prime primerange(n**2, (n+1)**2+1) - Bertrand's (proven): there is always a prime in the range primerange(n, 2*n) - Brocard's: there are at least four primes in the range primerange(prime(n)**2, prime(n+1)**2) The average gap between primes is log(n) [2]; the gap between primes can be arbitrarily large since sequences of composite numbers are arbitrarily large, e.g. the numbers in the sequence n! + 2, n! + 3 ... n! + n are all composite. References ========== 1. http://en.wikipedia.org/wiki/Prime_number 2. http://primes.utm.edu/notes/gaps.html Examples ======== >>> from sympy import primerange, sieve >>> print([i for i in primerange(1, 30)]) [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] The Sieve method, primerange, is generally faster but it will occupy more memory as the sieve stores values. The default instance of Sieve, named sieve, can be used: >>> list(sieve.primerange(1, 30)) [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] See Also ======== nextprime : Return the ith prime greater than n prevprime : Return the largest prime smaller than n randprime : Returns a random prime in a given range primorial : Returns the product of primes based on condition Sieve.primerange : return range from already computed primes or extend the sieve to contain the requested range. """ from sympy.functions.elementary.integers import ceiling # if we already have the range, return it if b <= sieve._list[-1]: for i in sieve.primerange(a, b): yield i return # otherwise compute, without storing, the desired range if a >= b: return # wrapping ceiling in int will raise an error if there was a problem # determining whether the expression was exactly an integer or not a = int(ceiling(a)) - 1 b = int(ceiling(b)) while 1: a = nextprime(a) if a < b: yield a else: return
def primerange(a, b): """ Generate a list of all prime numbers in the range [a, b). If the range exists in the default sieve, the values will be returned from there; otherwise values will be returned but will not modify the sieve. Notes ===== Some famous conjectures about the occurrence of primes in a given range are [1]: - Twin primes: though often not, the following will give 2 primes an infinite number of times: primerange(6*n - 1, 6*n + 2) - Legendre's: the following always yields at least one prime primerange(n**2, (n+1)**2+1) - Bertrand's (proven): there is always a prime in the range primerange(n, 2*n) - Brocard's: there are at least four primes in the range primerange(prime(n)**2, prime(n+1)**2) The average gap between primes is log(n) [2]; the gap between primes can be arbitrarily large since sequences of composite numbers are arbitrarily large, e.g. the numbers in the sequence n! + 2, n! + 3 ... n! + n are all composite. References ========== 1. https://en.wikipedia.org/wiki/Prime_number 2. http://primes.utm.edu/notes/gaps.html Examples ======== >>> from sympy import primerange, sieve >>> print([i for i in primerange(1, 30)]) [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] The Sieve method, primerange, is generally faster but it will occupy more memory as the sieve stores values. The default instance of Sieve, named sieve, can be used: >>> list(sieve.primerange(1, 30)) [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] See Also ======== nextprime : Return the ith prime greater than n prevprime : Return the largest prime smaller than n randprime : Returns a random prime in a given range primorial : Returns the product of primes based on condition Sieve.primerange : return range from already computed primes or extend the sieve to contain the requested range. """ from sympy.functions.elementary.integers import ceiling if a >= b: return # if we already have the range, return it if b <= sieve._list[-1]: for i in sieve.primerange(a, b): yield i return # otherwise compute, without storing, the desired range. # wrapping ceiling in as_int will raise an error if there was a problem # determining whether the expression was exactly an integer or not a = as_int(ceiling(a)) - 1 b = as_int(ceiling(b)) while 1: a = nextprime(a) if a < b: yield a else: return
def test_issue_13098(): assert floor(log(S('9.' + '9' * 20), 10)) == 0 assert ceiling(log(S('9.' + '9' * 20), 10)) == 1 assert floor(log(20 - S('9.' + '9' * 20), 10)) == 1 assert ceiling(log(20 - S('9.' + '9' * 20), 10)) == 2
def _intersect(self, other): from sympy.functions.elementary.integers import floor, ceiling if other.is_Interval and other.measure < S.Infinity: s = Range(ceiling(other.left), floor(other.right) + 1) return s.intersect(other) # take out endpoints if open interval return None
def test_ceiling(): assert ceiling(nan) is nan assert ceiling(oo) is oo assert ceiling(-oo) is -oo assert ceiling(zoo) is zoo assert ceiling(0) == 0 assert ceiling(1) == 1 assert ceiling(-1) == -1 assert ceiling(E) == 3 assert ceiling(-E) == -2 assert ceiling(2*E) == 6 assert ceiling(-2*E) == -5 assert ceiling(pi) == 4 assert ceiling(-pi) == -3 assert ceiling(S.Half) == 1 assert ceiling(Rational(-1, 2)) == 0 assert ceiling(Rational(7, 3)) == 3 assert ceiling(-Rational(7, 3)) == -2 assert ceiling(Float(17.0)) == 17 assert ceiling(-Float(17.0)) == -17 assert ceiling(Float(7.69)) == 8 assert ceiling(-Float(7.69)) == -7 assert ceiling(I) == I assert ceiling(-I) == -I e = ceiling(i) assert e.func is ceiling and e.args[0] == i assert ceiling(oo*I) == oo*I assert ceiling(-oo*I) == -oo*I assert ceiling(exp(I*pi/4)*oo) == exp(I*pi/4)*oo assert ceiling(2*I) == 2*I assert ceiling(-2*I) == -2*I assert ceiling(I/2) == I assert ceiling(-I/2) == 0 assert ceiling(E + 17) == 20 assert ceiling(pi + 2) == 6 assert ceiling(E + pi) == 6 assert ceiling(I + pi) == I + 4 assert ceiling(ceiling(pi)) == 4 assert ceiling(ceiling(y)) == ceiling(y) assert ceiling(ceiling(x)) == ceiling(x) assert unchanged(ceiling, x) assert unchanged(ceiling, 2*x) assert unchanged(ceiling, k*x) assert ceiling(k) == k assert ceiling(2*k) == 2*k assert ceiling(k*n) == k*n assert unchanged(ceiling, k/2) assert unchanged(ceiling, x + y) assert ceiling(x + 3) == ceiling(x) + 3 assert ceiling(x + k) == ceiling(x) + k assert ceiling(y + 3) == ceiling(y) + 3 assert ceiling(y + k) == ceiling(y) + k assert ceiling(3 + pi + y*I) == 7 + ceiling(y)*I assert ceiling(k + n) == k + n assert unchanged(ceiling, x*I) assert ceiling(k*I) == k*I assert ceiling(Rational(23, 10) - E*I) == 3 - 2*I assert ceiling(sin(1)) == 1 assert ceiling(sin(-1)) == 0 assert ceiling(exp(2)) == 8 assert ceiling(-log(8)/log(2)) != -2 assert int(ceiling(-log(8)/log(2)).evalf(chop=True)) == -3 assert ceiling(factorial(50)/exp(1)) == \ 11188719610782480504630258070757734324011354208865721592720336801 assert (ceiling(y) >= y) == True assert (ceiling(y) > y) == False assert (ceiling(y) < y) == False assert (ceiling(y) <= y) == False assert (ceiling(x) >= x).is_Relational # x could be non-real assert (ceiling(x) < x).is_Relational assert (ceiling(x) >= y).is_Relational # arg is not same as rhs assert (ceiling(x) < y).is_Relational assert (ceiling(y) >= -oo) == True assert (ceiling(y) > -oo) == True assert (ceiling(y) <= oo) == True assert (ceiling(y) < oo) == True assert ceiling(y).rewrite(floor) == -floor(-y) assert ceiling(y).rewrite(frac) == y + frac(-y) assert ceiling(y).rewrite(floor).subs(y, -pi) == -floor(pi) assert ceiling(y).rewrite(floor).subs(y, E) == -floor(-E) assert ceiling(y).rewrite(frac).subs(y, pi) == ceiling(pi) assert ceiling(y).rewrite(frac).subs(y, -E) == ceiling(-E) assert Eq(ceiling(y), y + frac(-y)) assert Eq(ceiling(y), -floor(-y)) neg = Symbol('neg', negative=True) nn = Symbol('nn', nonnegative=True) pos = Symbol('pos', positive=True) np = Symbol('np', nonpositive=True) assert (ceiling(neg) <= 0) == True assert (ceiling(neg) < 0) == (neg <= -1) assert (ceiling(neg) > 0) == False assert (ceiling(neg) >= 0) == (neg > -1) assert (ceiling(neg) > -3) == (neg > -3) assert (ceiling(neg) <= 10) == (neg <= 10) assert (ceiling(nn) < 0) == False assert (ceiling(nn) >= 0) == True assert (ceiling(pos) < 0) == False assert (ceiling(pos) <= 0) == False assert (ceiling(pos) > 0) == True assert (ceiling(pos) >= 0) == True assert (ceiling(pos) >= 1) == True assert (ceiling(pos) > 5) == (pos > 5) assert (ceiling(np) <= 0) == True assert (ceiling(np) > 0) == False assert ceiling(neg).is_positive == False assert ceiling(neg).is_nonpositive == True assert ceiling(nn).is_positive is None assert ceiling(nn).is_nonpositive is None assert ceiling(pos).is_positive == True assert ceiling(pos).is_nonpositive == False assert ceiling(np).is_positive == False assert ceiling(np).is_nonpositive == True assert (ceiling(7, evaluate=False) >= 7) == True assert (ceiling(7, evaluate=False) > 7) == False assert (ceiling(7, evaluate=False) <= 7) == True assert (ceiling(7, evaluate=False) < 7) == False assert (ceiling(7, evaluate=False) >= 6) == True assert (ceiling(7, evaluate=False) > 6) == True assert (ceiling(7, evaluate=False) <= 6) == False assert (ceiling(7, evaluate=False) < 6) == False assert (ceiling(7, evaluate=False) >= 8) == False assert (ceiling(7, evaluate=False) > 8) == False assert (ceiling(7, evaluate=False) <= 8) == True assert (ceiling(7, evaluate=False) < 8) == True assert (ceiling(x) <= 5.5) == Le(ceiling(x), 5.5, evaluate=False) assert (ceiling(x) >= -3.2) == Ge(ceiling(x), -3.2, evaluate=False) assert (ceiling(x) < 2.9) == Lt(ceiling(x), 2.9, evaluate=False) assert (ceiling(x) > -1.7) == Gt(ceiling(x), -1.7, evaluate=False) assert (ceiling(y) <= 5.5) == (y <= 5) assert (ceiling(y) >= -3.2) == (y > -4) assert (ceiling(y) < 2.9) == (y <= 2) assert (ceiling(y) > -1.7) == (y > -2) assert (ceiling(y) <= n) == (y <= n) assert (ceiling(y) >= n) == (y > n - 1) assert (ceiling(y) < n) == (y <= n - 1) assert (ceiling(y) > n) == (y > n)