ó Ąž™\c@ sxdZddlmZmZddlmZddlmZddlm Z ddl m Z m Z d ddd„ZdS( s5 Functions to support rewriting of SymPy expressions iĸĸĸĸ(tprint_functiontdivision(tExpr(task(tsubs(trebuildtunifyc s"t‡‡‡‡‡fd†}|S(sã Rewrite rule Transform expressions that match source into expressions that match target treating all `variables` as wilds. Examples ======== >>> from sympy.abc import w, x, y, z >>> from sympy.unify.rewrite import rewriterule >>> from sympy.utilities import default_sort_key >>> rl = rewriterule(x + y, x**y, [x, y]) >>> sorted(rl(z + 3), key=default_sort_key) [3**z, z**3] Use ``condition`` to specify additional requirements. Inputs are taken in the same order as is found in variables. >>> rl = rewriterule(x + y, x**y, [x, y], lambda x, y: x.is_integer) >>> list(rl(z + 3)) [3**z] Use ``assume`` to specify additional requirements using new assumptions. >>> from sympy.assumptions import Q >>> rl = rewriterule(x + y, x**y, [x, y], assume=Q.integer(x)) >>> list(rl(z + 3)) [3**z] Assumptions for the local context are provided at rule runtime >>> list(rl(w + z, Q.integer(z))) [z**w] c3 sđxētˆ|idˆƒD]˜}ˆrWˆgˆD]}|j||ƒ^q/Œ rWqnˆr|tˆj|ƒ|ƒ r|qnt|ƒˆƒ}t|tƒrŽt|ƒ}n|VqWdS(Nt variables(RtgetRtxreplaceRt isinstanceRR(texprt assumptionstmatchtvartexpr2(tassumet conditiontsourcettargetR(s2lib/python2.7/site-packages/sympy/unify/rewrite.pyt rewrite_rl.s,(tTrue(RRRRRR((RRRRRs2lib/python2.7/site-packages/sympy/unify/rewrite.pyt rewriterule s$ N((t__doc__t __future__RRtsympyRtsympy.assumptionsRtsympy.strategies.toolsRtsympy.unify.usympyRRtNoneR(((s2lib/python2.7/site-packages/sympy/unify/rewrite.pyts