py-sympy: Update to 1.6.2

Changelog:
1.6.2
Changes

    matrices
        Fixed a bug that made matrix operations fail in a multithreaded application. (#19812 by @pd0wm)

    polys
        Using factor with the extension argument no longer hangs in some cases. (#19847 by @jksuom and @rainwoodman)

    printing
        Calling preview with viewer="file" no longer looks for a file executable (a regression in 1.6.0) (#19904 by @eric-wieser)

        The deprecation of calling preview with viewer="StringIO" is now expired instead of forgotten (a regression in 1.6.0) (#19904 by @eric-wieser)

    other
        intersphinx links to :mod:`sympy` no longer point to the documentation for Immutable Matrices (#19881 by @eric-wieser and @oscarbenjamin)

1.6.1
Changes

    functions
        Fixes AttributeError in limit evaluation (#19604 by @sachin-4099)

    matrices
        Disabled default matrix intermediate product simplification and changed it to enable via context manager. (#19612 by @oscarbenjamin and @Pristine-Cat)

    simplify
        Fixes a bug in collect when collected symbols appear in the factorized expression. (#19601 by @mloubout and @oscarbenjamin)

    solvers
        Fixed exception handling in solveset's secondary trigonometric solver. (#19602 by @gschintgen and @oscarbenjamin)

    other
        SymPy is importable again in Python 3.5.1 (imports of typing.Type are removed) (#19620 by @oscarbenjamin)

        Fix the sphinx docs build for sphinx 3.1.1 (#19598 by @oscarbenjamin)

1.6

Backwards compatibility breaks and deprecations

Please manually add any backwards compatibility breaks or deprecations here, in addition to the automatic listing below.

    assumptions

        Removed deprecated Q.bounded (use Q.finite instead). Deprecated since version 1.0 (issue: #9425) (#18390 by @Smit-create)

        Removed deprecated Q.infinitesimal (use Q.zero instead). Deprecated since version 1.0 (issue: #9675) (#18390 by @Smit-create)

        Removed deprecated Q.infinity (use Q.infinte instead). Deprecated since version 1.0 (issue: #9426) (#18390 by @Smit-create)

    calculus
        Deprecated evaluate argument in differentiate_finite for making non-conservative finite differences. (#17881 by @vezeli)

    combinatorics
        Using Permutation.print_cyclic will raise deprecation warnings (#18033 by @oscarbenjamin, @souravgl0, and @sylee957)

    core

        Deprecated sympify automatically converting custom objects with __str__ or __repr__ implemented. (#19006 by @sylee957)

        BREAKING CHANGE: Basic.has no longer accepts strings as input. For example in SymPy 1.5 you could do Symbol('x').has('x') and the string 'x' passed to has would be sympified to a symbol so that the result would be True. In SymPy 1.6 this will raise an error because the string 'x' can not be sympified using strict sympification. (#19251 by @oscarbenjamin)

        Remove deprecated bounded, unbounded and infinitesimal. Deprecated since version 0.7.6 (issue #8071) (#18503 by @Smit-create)

        Relational is no longer a subclass of Expr and does not produce nonsensical results in arithmetic operations. This affects all Relational subclasses (Eq, Ne, Gt, Ge, Lt, Le). It is no longer possible to call meaningless Expr methods like as_coeff_Mul on Relational instances. (#18053 by @oscarbenjamin)

        Expr now uses cooperative dispatch for binary operations so it is possible for non-Expr Basic subclasses to override the behaviour of e.g. a + b where one of a or b is an instance of Expr. This also means that any non-Expr Basic subclasses can not depend on Expr.__add__ to create Add(a, b): if a class is not a subclass of Expr and wants to define binary operations with Expr it must do so explicitly in its own __add__ method. For classes depending on this this is not a backward compatible change. (#18116 by @oscarbenjamin)

    matrices
        The Matrix.is_zero property has been renamed to Matrix.is_zero_matrix.
        Matrix.is_zero is now always False. This is because in general is_zero means the number zero so a matrix can never be zero.

    To get the old behavior of M.is_zero in both old and new versions of sympy use from sympy.core.logic import fuzzy_and; fuzzy_and(m.is_zero for m in M). (#18464 by @sylee957)

    polys

        BREAKING CHANGE: Poly and PurePoly now subclass Basic rather than Expr. This means that they no longer have various Expr methods such as expand that do not make sense for Poly. Use as_expr to convert the Poly to an Expr before using Expr methods. (#18613 by @oscarbenjamin)

        BREAKING CHANGE: Poly instances with different domains now always compare unequal with p1 == p2 and p1.eq(p2). Previously Poly instances that had the same expression and generators would compare equal even if the domains were different. In some cases it might be necessary to specify the domain when comparing e.g. if p == Poly(x, x, domain='QQ'). (#18613 by @oscarbenjamin)

        DEPRECATION: Mixing Poly with non-polynomial Expr in binary operations is now deprecated. For example Poly(x, x) * exp(x) will give a deprecation warning but still return the Expr x*exp(x) as before. If the Expr can be converted to Poly (e.g. Poly(x, x) * x) then a Poly will be returned. To get an Expr always use the as_expr method first to convert the Poly to an Expr. To get a Poly always use as_poly to convert the Expr to a Poly. (#18613 by @oscarbenjamin)

        DEPRECATION: Passing Poly as the integrand to the integrate function or Integral class is now deprecated. Use the integrate method instead e.g. Poly(x, x).integrate(x) (#18613 by @oscarbenjamin)

    printing

        Removed deprecated Ccodeprinter (Use C89Printer or C99Printer instead). Deprecated since version 1.1 (Issue : #12220). (#18392 by @risubaba)

        Removed deprecated file viewer option in preview. Deprecated since version 0.7.3(Issue: #7018) (#18392 by @risubaba)

        Removed deprecated StringIO viewer option in preview. Deprecated since version 0.7.2(Issue: #7083) (#18392 by @risubaba)

    sets
        Set now uses cooperative dispatch for binary operations so it is possible for non-Set Basic subclasses to override the behaviour of e.g. a + b where one of a or b is an instance of Set. This also means that any non-Set Basic subclasses can not depend on e.g. Set.__add__ to create Union(a, b): if a class is not a subclass of Set and wants to define binary operations with Set it must do so explicitly in its own __add__ method. For classes depending on this this is not a backward compatible change. (#18116 by @oscarbenjamin)

    other
        Submodule names are no longer imported with from sympy import *. They can still be imported directly like from sympy import core or accessed like sympy.core, or like sys.modules['sympy.simplify'] for modules that share names with SymPy functions. (#18245 by @oscarbenjamve the T/F assumptions of a symbol or expression (#19155 by @smichr)

        common_assumptions returns the T/F assumptions in common amongst the given expressions (#19155 by @smichr)

        Added a refine_matrixelement function (#18681 by @Saanidhyavaeprecated Q.bounded (use Q.finite instead). Deprecated since version 1.0 (issue: #9425) (#18390 by @Smit-create)

        Removed deprecated Q.infinitesimal (use Q.zero instead). Deprecated since version 1.0 (issue: #9675) (#18390 by @Smit-create)

      ask(Q.antihermitian()) which earlier generated incorrect results. (#18303 by @czgdp1807)

        Improved code in ask function using constructs from cnf module. (#18204 by @JSS95 and @mcpl-sympy)

        Fixed bug in ask function: In case of user-defineus_domain now finds singularities in nested fractions (#19047 by @smichr and @ThomasHickman)

        singularities has been upgraded to handle more than rational functions (#19047 by @smichr and @ThomasHickman)

        fixes operations of AccumBounds (#18803 by @Ryand1234)

        periodicity of exponential functions with a non-zero phase component is now calculated. (#18746 by @mohitacecode)

        Correct the solution of differentiate_finite for expressions that contain embedded derivatives. (#17881 by @vezeli)

        Deprecated evaluate argument in differentiate_finite for making non-conservative finite differences. (#17881 by @vezeli)

        Updated docstrings of maximum, minimum, stationary_points and AccumBounds.intersection (#18581 by @mijo2)

        Fixes Recursion Error in AccumulationBounds.__pow__ by adding a check on denominator (#18450 by @Smit-create)

    combinatorics

        Permutation * PermutationGroup and PermutationGroup * Permutation return Coset. (#19139 by @mohitacecode)

        Added Coset Class. (#19077 by @mohitacecode and @sylee957)

        Added SymmetricPermutationGroup Class. (#19077 by @mohitacecode and @sylee957)

        Added schur number utilities in combinatorics (#18667 by @mijo2 and @slacker404)

        Raise exception with wrong size in Permutation. (#18587 by @Smit-create)

        Added Permutation.conjugacy_class and Permutation.conjugacy_classes for computing conjugacy classes in permutation groups. (#18354 by @lucjon and @sachin-4099)

        Fixed Permutation applying for negative integers. (#18032 by @mrocklin and @sylee957)

        Added Permutation.apply to use permutation as a symbolic function. (#18032 by @mrocklin and @sylee957)

        Using Permutation.print_cyclic will raise deprecation warnings (#18033 by @oscarbenjamin, @souravgl0, and @sylee957)
        Cycle class is no longer mutable and can be regarded as a sparse representation of a permutation (#17973 by @sachin-4099)

    core

        BREAKING CHANGE: Basic.has no longer accepts strings as input. For example in SymPy 1.5 you could do Symbol('x').has('x') and the string 'x' passed to has would be sympified to a symbol so that the result would be True. In SymPy 1.6 this will raise an error because the string 'x' can not be sympified using strict sympification. (#19251 by @oscarbenjamin)

        Mul.is_integer no longer rebuilds arguments into Mul (#19182 by @iammosespaulr)

        Mul with odd numerator and even denominator is recognized as rational but not integer (#19155 by @smichr)
        Deprecated sympify automatically converting custom objects with __str__ or __repr__ implemented. (#19006 by @sylee957)
        when strict=True, as_int will not convert True to 1 (#19054 by @smichr)
        Support mpmath.matrix in sympify. (#18911 by @smichr and @sylee957)
        Adds simplification to Pow._eval_nseries resolving incorrect limit evaluation (#18962 by @sachin-4099)
        doit(deep=False) now evaluates Add and Mul. (#18829 by @JSS95 and @mcpl-sympy)

        Reduces sensitivity of computation of order terms in Pow._eval_nseries (#18785 by @sachin-4099)

        Pow.is_zero is fixed for some cases involving infinite (or possibly infinite) expressions. (#18728 by @oscarbenjamin)

        Now finite and infinite are logical opposites in the old assumptions system so e.g. a Symbol declared with finite=False will have infinite=True. (#18726 by @oscarbenjamin)

        sympify no longer converts numpy arrays with size to scalars (#18651 by @mijo2 and @NeilGirdhar)

        __getnewargs__() added to Zero, One, NegativeOne, Half. (#18675 by @mohitacecode)

        simplification of powers with numerical products in the base is improved (#18650 by @sachin-4099)

        sqrt(x).is_negative is False when x is real (#18597 by @Smit-create)

        Add,_eval_as_leading_term() has been fixed (#18340 by @sachin-4099)

        Updated the definition of atoms method of class Basic (#18532 by @mijo2)

        basic - sorting in subs is improved so unsorted arguments will prefer replacing more complicated patterns first (e.g. the second derivative before the first derivative). (#18043 by @Psycho-Pirate)

        Remove deprecated bounded, unbounded and infinitesimal. Deprecated since version 0.7.6 (issue #8071) (#18503 by @Smit-create)

        Added check for AccumBounds. (#18478 by @smichr and @Smit-create)

        Adding gmpy in integer_nthroot ( It works only for n < 2**63) (#18380 by @Smit-create)

        Added new test case for relational (#18416 by @mijo2)

        Pow._eval_nseries fixed to accept all real exponents. (#18406 by @Smit-create)

        integer_ntroot and igcd now use gmpy when it is installed (#18276 by @Smit-create)

        Changed some partial derivatives like diff(f(g(x), h(x)), x) not to have dummy symbols. (#18326 by @sachin-4099)

        subs now works correctly with partial derivatives. (#18326 by @sachin-4099)

        Subclass of Function can inherit its nargs attribute to its subclasses. (#18258 by @JSS95 and @mcpl-sympy)

        Added try-except block in sympy/core/relational.py to handle NotImplementedError and return ConditionSet (#18211 by @Smit-create)

        Renamed core/evaluate to core/parameters (#18198 by @JSS95, @mcpl-sympy, and @oscarbenjamin)

        Added global_parameters, which is a thread-local storage for global parameters such as evaluate, distribute, etc. (#18198 by @JSS95, @mcpl-sympy, and @oscarbenjamin)

        Relational is no longer a subclass of Expr and does not produce nonsensical results in arithmetic operations. This affects all Relational subclasses (Eq, Ne, Gt, Ge, Lt, Le). It is no longer possible to call meaningless Expr methods like as_coeff_Mul on Relational instances. (#18053 by @oscarbenjamin)

        Expr now uses cooperative dispatch for binary operations so it is possible for non-Expr Basic subclasses to override the behaviour of e.g. a + b where one of a or b is an instance of Expr. This also means that any non-Expr Basic subclasses can not depend on Expr.__add__ to create Add(a, b): if a class is not a subclass of Expr and wants to define binary operations with Expr it must do so explicitly in its own __add__ method. For classes depending on this this is not a backward compatible change. (#18116 by @oscarbenjamin)

        Added global_evaluate[0] condition in add, sub, mul, div functions in Infinity class. (#18109 by @namannimmo10)

        Moved .as_poly() from Basic to Expr. (#18094 by @dhruvmendiratta6)

        Fixed a bug in Factors().as_expr() that led to simplifications that are not generally valid for complex numbers. (Exponents were always multiplied in power-of-a-power situations.) (#18087 by @gschintgen)
        Fix a regression in 1.5 that allowed expressions to compare equal to strings, and caused == to call str() on the other object. (#18057 by @asmeurer)

    functions

        Adjoint of exp and transpose of exp now work as expected. (#19151 by @akirakyle)

        Adds substitution to _eval_nseries() function of Abs() class resolving incorrect limit evaluations (#19037 by @sachin-4099)

        expand log term into its prime factors if the factor flag is True. (#18927 by @sbt4104)

        Evaluate nested floor/ceiling. (#18903 by @sbt4104)

        Update expand function for binomials. (#18802 by @sbt4104)

        periodicity of trigonometric functions with a non-zero phase component is now calculated. (#18746 by @mohitacecode)

        __getnewargs__() and args() added to IdentityFunction. (#18675 by @mohitacecode)

        Added _eval_nseries() functionality to hyper (#18630 by @dhruvmendiratta6)
        Fix number of terms in exp._eval_nseries. (#18598 by @mohitacecode)

        Fixes TypeError while using simplify (#18640 by @Smit-create)

        Added proportional tolerance for falling factorial test (#18456 by @mijo2)

        polygamma(n, 1/2) with n a positive integer is automatically evaluated (#18451 by @ethankward)

        floor and ceiling with float arguments now return Integers (#18424 by @mohitacecode)

        Sympified output numbers for factorial and binomial used with Mod. (#18339 by @namannimmo10)

        Maximum recursion depth is no longer exceeded when subfactorial is called on large numbers (#17983 by @sachin-4099)
        Copy edited the Special submodule to reflect the style guide for Google Season of Docs. (#17844 by @lglattly)

    geometry

        Line.bisectors will return the two perpendicular lines, bisecting the angles at the intersection of two linear entities and laying in the same plane as them (#19094 by @Jaime02 and @smichr)

        Added explicit optional parameters to Polygon and convex_hull (#15757 by @oscargus)

        Added bisectors method for Polygon class. (#18335 by @namannimmo10)

        Add __call__ method in Class Curve. (#18250 by @namannimmo10)

        Point.coordinates was added as a meaningful alias for Point.args (#18213 by @Jaime02)

    holonomic
        A cache mismatch error was fixed. (#19248 by @iammosespaulr and @smichr)

    integrals

        Handling Float Integrals (#18434 by @Smit-create)

        Added integration over summation (#18491 by @mijo2)

        Added extra step to evaluate integral if heurisch() returns None in heurisch_wrapper() (#18153 by @risubaba)

        Catch ValueError from meijerg() in _inverse_mellin_transform(). (#18141 by @Smit-create)

    logic

        boolalg (#18912 by @smichr)

        to_cnf/to_dnf (when simplify=True) require force=True` if there are more than 8 variables (#18912 by @smichr)

        simplify_logic recognizes trivial simplified cases (#18912 by @smichr)

        is_literal can treat Not as literal or not by using the literal_Not flag (#18912 by @smichr)

        Opposing Relationals are now detected correctly in nested Ands allowing evaluation to False in more cases. (#18811 by @oscarbenjamin)

        Added a new normal form - ANFform. Function ANFform converts a list of truth values to an expression in Algebraic Normal Form (ANF). (#13686 by @KonstantinTogoi)

        Added a new method BooleanFunction.to_anf that converts an expression to ANF by equivalent transformations. (#13686 by @KonstantinTogoi)

        Added a new function is_anf that checks if an expression is ANF. (#13686 by @KonstantinTogoi)

        Added a new function to_anf that converts an expression to ANF if it is not ANF. (#13686 by @KonstantinTogoi)

        Added a new function distribute_xor_over_and. Given a sentence s consisting of conjunction and exclusive disjunctions of literals, it returns an equivalent exclusive disjunction. (#13686 by @KonstantinTogoi)

        Added a new function bool_minterm that returns the k-th minterm of a fixed ordered set of binary variables. (#13686 by @KonstantinTogoi)

        Added a new function bool_maxterm that returns the k-th maxterm of a fixed ordered set of binary variables. (#13686 by @KonstantinTogoi)

        Added a new function bool_monomial that returns the k-th monomial of a fixed ordered set of binary variables. (#13686 by @KonstantinTogoi)

    matrices

        Fixed matrix creation from the list containg numpy ndarray. (e.g. Matrix([np.array([1, 2]), np.array([1, 2])])) (#19229 by @sylee957)

        Added is_strongly_diagonally_dominant and is_weakly_diagonally_dominant properties for Matrix. (#19205 by @sylee957)
        Powers of non-square matrices now always raise an error, even when constructed using MatPow(...). (#19104 by @jlherren)

        ZeroMatrix will not be logically False. (#19110 by @sbt4104)

        Added connected_components and connected_components_decomposition for matrix which decomposes a matrix into a block diagonal form. (#19045 by @sylee957)

        Added todok function to find dictionary of keys format from any dense or sparse matrices. (#19045 by @sylee957)

        Added BlockDiagMatrix.get_diag_blocks to provide an user API to get diagonal blocks from the matrix. (#19045 by @sylee957)

        Fixed bug of mpmath.matrix transforming into wrong shape if used to create Matrix. (#18911 by @smichr and @sylee957)

        Improved eigenvals and eigenvects for floating point matrices using mpmath. (#18911 by @smichr and @sylee957)

        Some expressions involving OneMatrix are now simplified. (#19009 by @jlherren)

        Indexing BlockMatrix now more often produces correct results and remains unevaluated if a correct simplification is not possible. (#19007 by @jlherren)

        Added a function that rotates matrices by 90 degrees (#18953 by @iammosespaulr and @sylee957)

        sparsetools - _doktocsr now returns a MutableSparseMatrix (#18940 by @smichr)

        Added Golub Kahan Bidiagonalization with Householder Reflections (#18797 by @sudoWin)

        Added test_solvers.py file which contains all the solvers-related tests. (#18793 by @guptabhaskar)

        Added evaluate option to MatAdd and MatMul (#18765 by @JSS95 and @mcpl-sympy)

        non-square matrices now raise NonSquareMatrixError if inversion is attempted (#18647 by @abhinav28071999)

        Added test_subspaces.py file which contain all the reductions-related tests. (#18713 by @mohitacecode)

        Added test_reductions.py file which contain all the reductions-related tests. (#18705 by @mohitacecode)

        Added test_eigen.py file which contain all the eigen-related tests. (#18690 by @mohitacecode)

        Added test_decomposition.py file which contain all the decomposition-related tests. (#18685 by @mohitacecode)

        Added test_determinant.py file which contain all the determinant-related tests. (#18668 by @mohitacecode)

        Faster Matrix Inverse using Block Matrix (#18608 by @abhinav28071999)

        Faster Matrix exponentiation using Cayley Hamilton Theorem (#18595 by @abhinav28071999)

        Fixed BlockDiagMatrix(A).blocks giving a non-block matrix. (#18621 by @abhinav28071999)

        Added dotprodsimp keyword to MatrixArithmetic.pow (#18600 by @Pristine-Cat)

        Implemented General Matrix Analytic functions (#18565 by @abhinav28071999)

        Enabled intermediate matrix product simplification to control expression blowup during certain matrix operations. (#18572 by @Pristine-Cat) (#18147 by @Pristine-Cat) (#18049 by @Pristine-Cat)

        Added environment variable check SYMPY_DOTPRODSIMP=0 to turn off the new dotprodsimp simplification in case the structure of the new results breaks user code. Should be removed after next live release. (#18572 by @Pristine-Cat)

        Pulled out and cleaned up many matrix function implementations from matrices.py into individual matrix source files determinant.py, reductions.py, subspaces.py, eigen.py, decompositions.py, solvers.py and inverse.py. (#18564 by @Pristine-Cat) (#18519 by @Pristine-Cat) (#18425 by @Pristine-Cat) (#18420 by @Pristine-Cat) (#18342 by @Pristine-Cat)

        Immutable matrices return themselves on call to as_immutable(). (#18441 by @Pristine-Cat)

        Fixed wrapper for NumPy matrices so SymPy iteration and indexing works correctly. (#18160 by @Pristine-Cat)

        Not backwards compatible: The Matrix.is_zero property has been renamed to Matrix.is_zero_matrix. Matrix.is_zero is now always False. This is because in general is_zero means the number zero so a matrix can never be zero. To get the old behavior of M.is_zero in both old and new versions of sympy use from sympy.core.logic import fuzzy_and; fuzzy_and(m.is_zero for m in M). (#18464 by @sylee957)

        Added PermutationMatrix and MatrixPermute for matrix permutations. (#18032 by @mrocklin and @sylee957)

        Fixed FunctionMatrix.replace raising TypeError: 'property' object is not iterable when the function is not a Lambda instance. (#17998 by @sylee957)

        FunctionMatrix and ElementwiseApplyFunction will always wrap the function inside Lambda. (#17998 by @sylee957)

        Cleaned up unnecessary slowdown for MatMul.doit when it contains explicit matrices. (#17872 by @sylee957)

        Fixed MatPow(Inverse(A), 3) and Inverse(MatPow(A, 3)) canonicalized into different objects. (#17872 by @sylee957)
        Improved inversion of block matrices by selecting an appropriate formula. (#19215 by @jlherren)

    ntheory

        the number of digits (like bit length) can now be specified for digits (#18961 by @Arpan612 and @smichr)

        Corrects the condition for "Extra strong" Lucas pseudoprime (#18946 by @Arpan612 and @sylee957)

        count_digits works only with numbers (not strings) (#18807 by @smichr)

        digits is now located in digits instead of factor_ (#18807 by @smichr)

        implemented elliptic curve (#18682 by @abhinav28071999 and @shikil)

        added new ntheory module digits.py containing methods related to arithmetic properties of integers (currently, frequency counters for digits of integers, palindromic numbers) (#18659 by @sr-murthy)

        Made divisor_sigma() symbolically recognize the case: divisor_sigma(a**j*b**k) (#18688 by @sachin-4099)

        Added multiplicty_in_factorial(p, n) to find the multiplicity of p in n! without calculating the factorial. (#18671 by @sachin-4099)

        implemented gaussian prime test (#18673 by @abhinav28071999)

        is_nthpow_residue no longer raises ValueError when a < 0 (#18398 by @abhinav28071999)

        polynomial_congruence recognizes x**n + a = 0 mod m as a special case (#18398 by @abhinav28071999)

        Added polynomial_congruence(expr, m) to find values congruent (mod m) to a polynomial (#18294 by @abhinav28071999)

        is_nthpow_residue handles numbers that are not powers of a primitive root. (#18337 by @abhinav28071999)

        Fixes nthroot_mod for prime powers (#18274 by @abhinav28071999)

        nthroot_mod now supports composite moduli (#18199 by @abhinav28071999)

        Added dra and drm to calculate digital root via addition and multiplication (#16496 by @abhinav28071999 and @smichrinav28071999)

        Make nthroot_mod , primitive_root and _primitive_root_prime_iter incompatible with composite modulo. (#18194 by @risubaba)

        In def _sqrt_mod_prime_power(a, p, k): it is assumed that p is a prime number. And this function caled check for zero in is_nthpow_residue. (#18129 by @erdOne)
        Added proper_divisor and proper_divisor_count functions (#18085 by @adhoc-king and @czgdp1807)
        Proper exception when accessing index 0 of sieve. (#18013 by @JulienPalard)

    parsing

        added support for unary operators: unary plus(+), unary minus(-), pre/post increment(++), pre/post decrement(--) and logical NOT(!) in C parser (#19140 by @smitgajjar)

        added support for parenthesized expression in C parser (#19140 b as_expr method first to convert the Poly to an Expr. To get a Poly always use as_poly to convert the Expr to a Poly. (#18613 by @oscarbenjamin)

        DEPRECATION: Passing Poly as the integrand to the integrate function or Integral class is now deprecated. Use the integrate method instead e.g. Poly(x, x).integrate(x) (#18613 by @oscarbenjamin)

        add condition for f == 0 to Piecewise solution for symbolic quartic polynomials (#18571 by @harsh9200)

        Fixed polynomial gcd bug (#18566 by @Smit-create)

        Added check for expressions containing GoldenRatio and TribonacciConstant (#18535 by @Smit-create)

        Added expand in simplify method of ExpressionDomain (#18472 by @Smit-create)

        Fixed the issue of cancel not expanding the product of irrational conjugates and added Tests (#18448 by @iamabhishek0)

        Prevent creation of CC from changing the context of RealElement. (#18312 by @V1krant)

        Changes in Poly.__new__() to make it handle simplified Matrix (#18159 by @Smit-create)

        interpolate will no longer return nan when x is a supplied coordinate (#18030 by @smichr)

        interpolating_poly will raise an error if x is not symbolic (#18030 by @smichr)

        interpolating_poly will raise an error if X or Y depend on x (#18030 by @smichr)

        interpolating-poly will now use only the first n points in X and Y (#18030 by @smichr)

        Added KSY_precondition() to test for the Kapur-Saxena-Yang precondition (#17974 by @ctsiagkalis)

        Added get_KSY_Dixon_resultant() and auxiliary methods for computing the KSY approach to Dixon's Resultant (#17974 by @ctsiagkalis)

    printing
        the inverse hyperbolic functions now respect the inv_trig_style printer setting (#19235 by @eric-wieser)

        Fixed numpy printer raising error for unevaluated numeric power. (#19170 by @sylee957)

        Fixed IdentityFunction printing for LaTeX. (#19032 by @sylee957)

        Added parenthesize_super option to LatexPrinter. (#18256 by @JSS95 and @mcpl-sympy)

        Removing python2 support from PythonCodePrinter (#18381 by @Smit-create)

        Added support for airy functions in the SciPyPrinter class. (#18908 by @OmarWagih1)

        allowed ReprPrinter to maintain original expr order via turning ordering off (#18777 by @leerobert)

        Fix lambdify with Min for arrays of more than one dimension (#18774 by @sbt4104)

        Fixed MatMul with complex coefficients raising error when printed. (#18744 by @sylee957)

        fixes incorrect parenthesizes in latex print of integral (#18772 by @Ryand1234)

        fixes nested differentiation problem in latex format (#18740 by @Ryand1234)

        added Python printer for KroneckerDelta (#18185 by @m93a)

        Added min and max options for printers thod of undetermined coefficients. (#18410 by @Mohitbalwani26)

        Fixed checkodesol for some cases when the solution returned by variation of parameters was correct but chekodesol couldn't simplify it. (#18376 by @Mohitbalwani26)

        Fixed dsolve for some cases of linear non-homogeneous ODEs when using the method of undetermined coefficients. (#18309 by @Mohitbalwani26)

        Changed return type from None to [], as in #18199 the return type of nth_root was changed when all_root = True and no root exists (#18285 by @abhinav28071999)

        ode.py - solve function is used to express the equation in factorised form (#18214 by @Mohitbalwani26 and @smichr)

        Fixed a bug in diophantine where negative coefficients could lead to incomplete sction with permute=True. (#18200 by @gschintgen)

        The diophantine solver no longer raises for unsympified inputs. (#18201 by @oscarbenjamin)

        fixed a bug in diophantine when using permute=True which caused incomplete permutations to be returned (#18189 by @abhinav28071999)

        diophantine.py - fixed bug where AttributeError was raised in some cases. (#18167 by @Mohitbalwani26)

        Solving of hyperbolic equations improved in solveset. (#14053 by @gschintgen, @ishanaj, @oscarbenjamin, and @oscargus)
        Copy edited solvers.py to reflect the style guide for Google Season of Docs. (#17921 by @lglattly)

    stats

        Allowing the user to define custom distributions (#19123 by @Smit-create)

        Added coskewness (#18935 by @Smit-create)

        Added sampling methods for discrete random variables (#18289 by @Smit-create)

        Added median function. (#18300 by @Smit-create)

        Updated some documentation in NormalGamma and JointRV functions (#18589 by @akash9712 8336 by @Smit-create)

        Fixed domain bug in probability method of ContinuousPspace in sympy/stats/crv.py (#18311 by @Smit-create)

        Added Bernoulli Process in sympy/stats/stochastic_process_types.py (#18173 by @Smit-create)

        Added Heger bound (#18605 by @Smit-create)

        Implemented derivatives with respect to symbols in tensor expressions (#18093 by @joha2 and @Upabjojr)

        Implemented derivatives with respect to tensors in tensor expressions (#18093 by @joha2 and @Upabjojr)

        Added _eval_simplify method for class ImmutableDenseNDimArray (#18369 by @iamabhishek0)

        Fixing bug in replacing indices in PartialDerivative tensor objects. (#18242 by @Upabjojr)

        Tensor module: refactory to allow mixing PartialDerivative and TensAdd. (#18224 by @Upabjojr)

        Fix PartialDerivative operator to correctly handle the valence (covariant/contravariant) of the deriving variable. (#18166 by @Upabjojr)

        .dummy_fmt changed to .dummy_name (#17518 by @drybalka)

        metric parameter for TensorIndexType is now split into 2 optional parameters metric_name and metric_symmetry (#17518 by @drybalka)

        TensorIndexType.dim is now a symbol and not None (#17518 by @drybalka)

utilities

        Overflow condition and negative argument for 'ibin' added (#18973 by @Arpan612)

        iterables - uniq will now raise a RuntimeError if a size change of the sequence is detected (#18835 by @smichr)

        iterables now includes is_palindromic to check if a sequence (or slice thereof) is palindromic (#18807 by @smichr)

        iterables: generate_derangements now handles unsorted input correctly (#18810 by @smichr)

        Code for the test runner is moved to a new sympy.testing package. (#18095 by @oscarbenjamin)

        lambdify: avoid using scipy versions of numpy functions, which are deprecated, in lambdify. (#18080 by @sylee957)

    other

        Replace inspect.getargspec with getfullargspec (#18784 by @sethtroisi)

        Updated README to include details about how to install SymPy using PyPI (#18518 by @mijo2)

        Corrected an inconsistency in the "Advanced Expression Manipulation" section of the tutorial. (#18287 by @Smit-create)

        Submodule names are no longer imported with from sympy import *. They can still be imported directly like from sympy import core or accessed like sympy.core, or like sys.modules['sympy.simplify'] for modules that share names with SymPy functions. (#18245 by @oscarbenjamin)

        README.rst - Added the codecov Badge in readme.rst (#18266 by @Mohitbalwani26)

        updated the README.rst and doc/README.rst with links to the SymPy Documentation Style Guide. (#17922 by @lglattly)


(ryoon)