ó ¡¼™\c@ s‘dZddlmZmZddlmZddlmZed„Zd„Z ed„Z d „Z d „Z d „Z ed „Zd „ZdS(sP Generic Rules for SymPy This file assumes knowledge of Basic and little else. iÿÿÿÿ(tprint_functiontdivision(tsifti(tnewc s‡‡fd†}|S(s” Create a rule to remove identities isid - fn :: x -> Bool --- whether or not this element is an identity >>> from sympy.strategies import rm_id >>> from sympy import Basic >>> remove_zeros = rm_id(lambda x: x==0) >>> remove_zeros(Basic(1, 0, 2)) Basic(1, 2) >>> remove_zeros(Basic(0, 0)) # If only identites then we keep one Basic(0) See Also: unpack c sœttˆ|jƒƒ}t|ƒdkr.|St|ƒt|ƒkrˆ|jgt|j|ƒD]\}}|sb|^qbŒSˆ|j|jdƒSdS(s Remove identities iN(tlisttmaptargstsumtlent __class__tzip(texprtidstargtx(tisidR(s2lib/python2.7/site-packages/sympy/strategies/rl.pyt ident_removes 2((RRR((RRs2lib/python2.7/site-packages/sympy/strategies/rl.pytrm_id s c s‡‡‡fd†}|S(s Create a rule to conglomerate identical args >>> from sympy.strategies import glom >>> from sympy import Add >>> from sympy.abc import x >>> key = lambda x: x.as_coeff_Mul()[1] >>> count = lambda x: x.as_coeff_Mul()[0] >>> combine = lambda cnt, arg: cnt * arg >>> rl = glom(key, count, combine) >>> rl(Add(x, -x, 3*x, 2, 3, evaluate=False)) 3*x + 5 Wait, how are key, count and combine supposed to work? >>> key(2*x) x >>> count(2*x) 2 >>> combine(2, x) 2*x c s˜t|jˆƒ}t‡fd†|jƒDƒƒ}g|jƒD]\}}ˆ||ƒ^qA}t|ƒt|jƒkrtt|ƒ|ŒS|SdS(s2 Conglomerate together identical args x + x -> 2x c3 s0|]&\}}|ttˆ|ƒƒfVqdS(N(RR(t.0tkR(tcount(s2lib/python2.7/site-packages/sympy/strategies/rl.pys DsN(RRtdicttitemstsetRttype(R tgroupstcountstmattcnttnewargs(tcombineRtkey(s2lib/python2.7/site-packages/sympy/strategies/rl.pyt conglomerateAs ".((RRRR ((RRRs2lib/python2.7/site-packages/sympy/strategies/rl.pytglom)s c s‡‡fd†}|S(sÇ Create a rule to sort by a key function >>> from sympy.strategies import sort >>> from sympy import Basic >>> sort_rl = sort(str) >>> sort_rl(Basic(3, 1, 2)) Basic(1, 2, 3) c sˆ|jt|jdˆƒŒS(NR(R tsortedR(R (RR(s2lib/python2.7/site-packages/sympy/strategies/rl.pytsort_rlWs((RRR#((RRs2lib/python2.7/site-packages/sympy/strategies/rl.pytsortMs c s‡‡fd†}|S(sW Turns an A containing Bs into a B of As where A, B are container types >>> from sympy.strategies import distribute >>> from sympy import Add, Mul, symbols >>> x, y = symbols('x,y') >>> dist = distribute(Mul, Add) >>> expr = Mul(2, x+y, evaluate=False) >>> expr 2*(x + y) >>> dist(expr) 2*x + 2*y c s‘xŠt|jƒD]y\}}t|ˆƒr|j| |j||j|d}}}ˆg|jD]}ˆ||f|Œ^qeŒSqW|S(Ni(t enumerateRt isinstance(R tiR tfirsttbttail(tAtB(s2lib/python2.7/site-packages/sympy/strategies/rl.pyt distribute_rlks -5((R+R,R-((R+R,s2lib/python2.7/site-packages/sympy/strategies/rl.pyt distribute[sc s‡‡fd†}|S(s Replace expressions exactly c s|ˆkrˆS|SdS(N((R (taR)(s2lib/python2.7/site-packages/sympy/strategies/rl.pytsubs_rlus ((R/R)R0((R/R)s2lib/python2.7/site-packages/sympy/strategies/rl.pytsubssscC s(t|jƒdkr |jdS|SdS(s Rule to unpack singleton args >>> from sympy.strategies import unpack >>> from sympy import Basic >>> unpack(Basic(2)) 2 iiN(RR(R ((s2lib/python2.7/site-packages/sympy/strategies/rl.pytunpack~s cC sb|j}g}x@|jD]5}|j|krA|j|jƒq|j|ƒqW||j|ŒS(s9 Flatten T(a, b, T(c, d), T2(e)) to T(a, b, c, d, T2(e)) (R Rtextendtappend(R RtclsRR ((s2lib/python2.7/site-packages/sympy/strategies/rl.pytflatten‹s cC s?y&t|ƒttt|jƒƒŒSWntk r:|SXdS(sÅ Rebuild a SymPy tree This function recursively calls constructors in the expression tree. This forces canonicalization and removes ugliness introduced by the use of Basic.__new__ N(RRRtrebuildRt Exception(R ((s2lib/python2.7/site-packages/sympy/strategies/rl.pyR7–s& N(t__doc__t __future__RRtsympy.utilities.iterablesRtutilRRR!R$R.R1R2R6R7(((s2lib/python2.7/site-packages/sympy/strategies/rl.pyts  $