Re: Radicals simplify

*To*: mathgroup at smc.vnet.net*Subject*: [mg106439] Re: Radicals simplify*From*: dh <dh at metrohm.com>*Date*: Tue, 12 Jan 2010 05:16:35 -0500 (EST)*References*: <hic37h$5ef$1@smc.vnet.net> <201001111030.FAA23508@smc.vnet.net> <higdmv$kir$1@smc.vnet.net>

Hi Murray, stright from the manual: "With the default setting ComplexityFunction->Automatic, forms are ranked primarily according to their LeafCount, with corrections to treat integers with more digits as more complex." Daniel Murray Eisenberg wrote: > Mathematica 7 documentation does NOT say that LeafCount is the criterion > for determining simplicity, that is, the default value of > ComplexityFunction. Rather it says: > > "The default ComplexityFunction counts the subexpressions and digits > of integers." > > But it does not even say how it combines the counts of the number of > subexpressions and digits of integers! > > On 1/11/2010 5:30 AM, dh wrote: >> Hi, >> >> why do you think x(x^2 y^3)^(1/4) is simpler than (x^6 y^3)^(1/4)? >> >> Mathematica needs some criterion for this decision. The default criterion is the >> >> "LeafCount[..]". If that does not suit you, you must define another >> >> criterion. >> >> Daniel >> >> >> >> francix wrote: >> >>> Hi, >>> I am using Matematica 7 and need some help with Radicals. >>> If I do >>> Simplify[(x^4 y^3)^(1/4), x>= 0] I correctly have >>> x (y^3)^(1/4) >>> But If I do >>> Simplify[(x^6 y^3)^(1/4), x>= 0] I get >>> (x^6 y^3)^(1/4) and not the correct answer x(x^2 y^3)^(1/4) >>> Thanks in advanced. >> >> >

**Follow-Ups**:**Re: Re: Radicals simplify***From:*Murray Eisenberg <murray@math.umass.edu>

**References**:**Re: Radicals simplify***From:*dh <dh@metrohm.com>