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0.7.4.1 These are the release notes for SymPy 0.7.4.1, which was released on December 15, 2013. This version of SymPy has been tested on Python 2.6, 2.7, 3.2, 3.3, and PyPy. This was a small bugfix release to fix an import issue on Windows (https://github.com/sympy/sympy/issues/2681). 0.7.4 These are the release notes for SymPy 0.7.4, which was released on December 9, 2013. This version of SymPy has been tested on Python 2.6, 2.7, 3.2, 3.3, and PyPy. Major changes Python 3 SymPy now uses a single code-base for Python 2 and Python 3. Geometric Algebra The internal representation of a multivector has been changes to more fully use the inherent capabilities of SymPy. A multivector is now represented by a linear combination of real commutative SymPy expressions and a collection of non-commutative SymPy symbols. Each non-commutative symbol represents a base in the geometric algebra of an N-dimensional vector space. The total number of non-commutative bases is 2**N - 1 (N of which are a basis for the vector space) which when including scalars give a dimension for the geometric algebra of 2**N. The different products of geometric algebra are implemented as functions that take pairs of bases symbols and return a multivector for each pair of bases. The LaTeX printing module for multivectors has been rewritten to simply extend the existing sympy LaTeX printing module and the sympy LaTeX module is now used to print the bases coefficients in the multivector representation instead of writing an entire LaTeX printing module from scratch. The main change in the geometric algebra module from the viewpoint of the user is the inteface for the gradient operator and the implementation of vector manifolds: The gradient operator is now implemented as a special vector (the user can name it grad if they wish) so the if F is a multivector field all the operations of grad on F can be written grad*F, F*grad, grad^F, F^grad, grad|F, F|grad, grad<F, F<grad, grad>F, and F>grad where **, ^, |, <, and > are the geometric product, outer product, inner product, left contraction, and right contraction, respectively. The vector manifold is defined as a parametric vector field in an embedding vector space. For example a surface in a 3-dimensional space would be a vector field as a function of two parameters. Then multivector fields can be defined on the manifold. The operations available to be performed on these fields are directional derivative, gradient, and projection. The weak point of the current manifold representation is that all fields on the manifold are represented in terms of the bases of the embedding vector space. Classical Cryptography Implements: Affine ciphers Vigenere ciphers Bifid ciphers Hill ciphers RSA and "kid RSA" linear feedback shift registers. Common Subexpression Elimination (CSE) Major changes have been done in cse internals resulting in a big speedup for larger expressions. Some changes reflect on the user side: Adds and Muls are now recursively matched ([w*x, w*x*y, w*x*y*z] ǹow turns into [(x0, w*x), (x1, x0*y)], [x0, x1, x1*z]) CSE is now not performed on the non-commutative parts of multiplications (it avoids some bugs). Pre and post optimizations are not performed by default anymore. The optimizations parameter still exists and optimizations='basic' can be used to apply previous default optimizations. These optimizations could really slow down cse on larger expressions and are no guarantee of better results. An order parameter has been introduced to control whether Adds and Muls terms are ordered independently of hashing implementation. The default order='canonical' will independently order the terms. order='none' will not do any ordering (hashes order is used) and will represent a major performance improvement for really huge expressions. In general, the output of cse will be slightly different from the previous implementation. Diophantine Equation Module This is a new addition to SymPy as a result of a GSoC project. With the current release, following five types of equations are supported. Linear Diophantine equation, a_{1}x_{1} + a_{2}x_{2} + . . . + a_{n}x_{n} = b General binary quadratic equation, ax^2 + bxy + cy^2 + dx + ey + f = 0 Homogeneous ternary quadratic equation, ax^2 + by^2 + cz^2 + dxy + eyz + fzx = 0 Extended Pythagorean equation, a_{1}x_{1}^2 + a_{2}x_{2}^2 + . . . + a_{n}x_{n}^2 = a_{n+1}x_{n+1}^2 General sum of squares, x_{1}^2 + x_{2}^2 + . . . + x_{n}^2 = k Unification of Sum, Product, and Integral classes A new superclass has been introduced to unify the treatments of indexed expressions, such as Sum, Product, and Integral. This enforced common behavior accross the objects, and provides more robust support for a number of operations. For example, Sums and Integrals can now be factored or expanded. S.subs() can be used to substitute for expressions inside a Sum/Integral/Product that are independent of the index variables, including unknown functions, for instance, Integral(f(x), (x, 1, 3)).subs(f(x), x**2), while Sum.change_index() or Integral.transform are now used for other changes of summation or integration variables. Support for finite and infinite sequence products has also been restored. In addition there were a number of fixes to the evaluation of nested sums and sums involving Kronecker delta functions, see issue 3924 and issue 3987. Series The Order object used to represent the growth of a function in series expansions as a variable tend to zero can now also represent growth as a variable tend to infinity. This also fixed a number of issues with limits. See issue 234 and issue 2670. Division by Order is disallowed, see issue 1756. Addition of Order object is now commutative, see issue 1180. Physics Initial work on gamma matrices, depending on the tensor module. Logic New objects true and false which are Basic versions of the Python builtins True and False. Other Arbitrary comparisons between expressions (like x < y) no longer have a boolean truth value. This means code like if x < y or sorted(exprs) will raise TypeError if x < y is symbolic. A typical fix of the former is if (x < y) is True (assuming the if block should be skipped if x < y is symbolic), and of the latter is sorted(exprs, key=default_sort_key), which will order the expressions in an arbitrary, but consistent way, even across platforms and Python versions. See issue 2832. Arbitrary comparisons between complex numbers (for example, I > 1) now raise TypeError as well (see PR #2510). minpoly now works with algebraic functions, like minpoly(sqrt(x) + sqrt(x + 1), y). exp can now act on any matrix, even those which are not diagonalizable. It is also more comfortable to call it, exp(m) instead of just m.exp(), as was required previously. sympify now has an option evaluate=False that will not automatically simplify expressions like x+x. Deep processing of cancel and simplify functions. simplify is now recursive through the expression tree. See e.g. issue 3923. Improved the modularity of the codebase for potential subclasses, see issue 3652. The SymPy cheatsheet was cleaned up. Backwards compatibility breaks and deprecations Removed deprecated Real class and is_Real property of Basic, see issue 1721. Removed deprecated 'each_char' option for symbols(), see issue 1919. The viewer="StringIO" option to preview() has been deprecated. Use viewer="BytesIO" instead. See issue 3984. TransformationSet has been renamed to ImageSet. Added public facing imageset function. 0.7.3 These are the release notes for SymPy 0.7.3, which was released on July 13, 2013. It can be downloaded from https://github.com/sympy/sympy/releases/tag/sympy-0.7.3. This version of SymPy has been tested on Python 2.5, 2.6, 2.7, 3.2, 3.3, and PyPy. Major changes Integration This release includes Risch integration algorithm from Aaron Meurer's 2010 Google Summer of Code project. This makes integrate much more powerful and much faster for the supported functions. The algorithm is called automatically from integrate(). For now, only transcendental elementary functions containing exp or log are supported. To access the algorithm directly, use integrate(expr, x, risch=True). The algorithm has the ability to prove that integrals are nonelementary. To determine if a function is nonelementary, integrate using risch=True. If the resulting Integral class is an instance of NonElementaryIntegral, then it is not elementary (otherwise, that part of the algorithm has just not been implemented yet). Here is an example integral that could not be computed before: >>> f = x*(x + 1)*(2*x*(x - (2*x**3 + 2*x**2 + x + 1)*log(x + 1))*exp(3*x**2) + (x**2*exp(2*x**2) - log(x + 1)**2)**2)/((x + 1)*log(x + 1)**2 - (x**3 + x**2)*exp(2*x**2))**2 >>> integrate(f, x) x + x*exp(x**2)*log(x + 1)/(x**2*exp(2*x**2) - log(x + 1)**2) - log(x + 1) - log(exp(x**2) - log(x + 1)/x)/2 + log(exp(x**2) + log(x + 1)/x)/2 ODE Built basic infrastructure of the PDE module (PR #1970) Theano Interaction SymPy expressions can now be translated into Theano expressions for numeric evaluation. This includes most standard scalar operations (e.g. sin, exp, gamma, but not beta or MeijerG) and matrices. This system generally outperforms lambdify and autowrap but does require Theano to be installed. Matrix Expressions Assumptions Matrix expressions now support inference using the new assumptions system. New predicates include invertible, symmetric, positive_definite, orthogonal, .... New Operators New operators include Adjoint, HadamardProduct, Determinant, MatrixSlice, DFT. Also, preliminary support exists for factorizations like SVD and LU. Context manager for New Assumptions Added the with assuming(*facts) context manager for new assumptions. See blogpost Backwards compatibility breaks and deprecations This is the last version of SymPy to support Python 2.5. The IPython extension, i.e., %load_ext sympy.interactive.ipythonprinting is deprecated. Use from sympy import init_printing; init_printing() instead. See issue 3914. The viewer='file' option to preview without a file name is deprecated. Use filename='name' in addition to viewer='file'. See issue 3919. The deprecated syntax Symbol('x', dummy=True), which had been deprecated since 0.7.0, has been removed. Use Dummy('x') or symbols('x', cls=Dummy) instead. See issue 3378. The deprecated Expr methods as_coeff_terms and as_coeff_factors, which have been deprecated in favor of as_coeff_mul and as_coeff_add, respectively (see also as_coeff_Mul and as_coeff_Add), were removed. The methods had been deprecated since SymPy 0.7.0. See issue 3377. The spherical harmonics have been completely rewritten. See PR #1510. Minor changes Solvers Added enhancements and improved the methods of solving exact differential equation ((PR #1955)) and ((PR #1823)) Support for differential equations with linear coefficients and those that can be reduced to separable and linear form ((PR #1940), (PR #1864), (PR #1883)) Support for first order linear general PDE's with constant coefficients ((PR #2109)) Return all found independent solutions for underdetermined systems. Handle recursive problems for which y(0) = 0. Handle matrix equations. Integration integrate will split out integrals into Piecewise expressions when conditions must hold for the answer to be true. For example, integrate(x**n, x) now gives Piecewise((log(x), Eq(n, -1), (x**(n + 1)/(n + 1), True)) (previously it just gave x**(n + 1)/(n + 1)) Calculate Gauss-Legendre and Gauss-Laguerre points and weights (PR #1497) Various new error and inverse error functions (PR #1703) Use in heurisch for more symmetric and nicer results Gruntz for expintegrals and all new erf* Li, li logarithmic integrals (PR #1708) Integration of li/Li by heurisch (PR #1712) elliptic integrals, complete and incomplete Integration of complete elliptic integrals by meijerg Integration of Piecewise with symbolic conditions. Fixed many wrong results of DiracDelta integrals. Logic Addition of SOPform and POSform functions to sympy.logic to generate boolean expressions from truth tables. Addition of simplify_logic function and enabling simplify() to reduce logic expressions to their simplest forms. Addition of bool_equals function to check equality of boolean expressions and return a mapping of variables from one expr to other that leads to the equality. Addition of disjunctive normal form methods - to_dnf, is_dnf Others gmpy version 2 is now supported Added is_algebraic_expr() method (PR #2176) Many improvements to the handling of noncommutative symbols: Better support in simplification functions, e.g. factor, trigsimp Better integration with Order() Better pattern matching Improved pattern matching including matching the identity. normalizes Jacobi polynomials Quadrature rules for orthogonal polynomials in arbitrary precision (hermite, laguerre, legendre, gen_legendre, jacobi) summation of harmonic numbers Many improvements of the polygamma functions evaluation at special arguments Connections to harmonic numbers structured full partial fraction decomposition (mainly interesting for developers) besselsimp improvements Karr summation convention New spherical harmonics improved minimal_polynomial using composition of algebraic numbers (PR #2038) faster integer polynomial factorization (PR #2148) Euler-Descartes method for quartic equations (PR #1947) algebraic operations on tensors (PR #1700) tensor canonicalization (PR #1644) Handle the simplification of summations and products over a KroneckerDelta. Implemented LaTeX printing of DiracDelta, Heaviside, KroneckerDelta and LeviCivita, also many Matrix expressions. Improved LaTeX printing of fractions, Mul in general. IPython integration and printing issues have been ironed out. Stats now supports discrete distributions (e.g. Poisson) by relying on Summation objects Added DOT printing for visualization of expression trees Added information about solvability and nilpotency of named groups.
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$NetBSD: distinfo,v 1.8 2014/01/21 08:38:04 wiz Exp $
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SHA1 (sympy-0.7.4.1.tar.gz) = 073b2ddf7ee8bc2b9e3687660d59e8848d6fce6c
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RMD160 (sympy-0.7.4.1.tar.gz) = 087661c59a8f75bee74241ff952dc3ca5f9a84e1
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Size (sympy-0.7.4.1.tar.gz) = 6824862 bytes
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