[Date Index]
[Thread Index]
[Author Index]
Re: Simplify problem
*To*: mathgroup at smc.vnet.net
*Subject*: [mg95805] Re: Simplify problem
*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
*Date*: Wed, 28 Jan 2009 06:26:35 -0500 (EST)
*Organization*: The Open University, Milton Keynes, UK
*References*: <glmstk$mm3$1@smc.vnet.net>
In article <glmstk$mm3$1 at smc.vnet.net>, tidy512 at googlemail.com wrote:
> I am using Simplify / FullSimplify etc. to simplify some equations
> I have, but I am unable to coerce Mathematica into automatically
> giving me the form I require for some of the sub-expressions, e.g.
>
> I'd like
>
> 1/Sqrt[1 + 1/x]
>
> to be automatically converted to
>
> Sqrt[x/(1 + x)]
>
> 'x' is always of type Real and greater-than 0 btw.
>
> I would appreciate any help or tips anyone can provide on this.
Broadly speaking, Mathematica mainly uses *LeafCount* to assess the
complexity of expressions. For instance, of two expressions, the one
with the lowest value for *LeafCount* will be deemed as simpler than the
other.
In[2]:= 1/Sqrt[1 + 1/x] // LeafCount
Out[2]= 9
In[3]:= Sqrt[x/(1 + x)] // LeafCount
Out[3]= 11
So Simmplify/FullSimplify is not going to go from the first from to the
second except if one can modify/write appropriately the complexity
function used by FullSimplify. See
http://reference.wolfram.com/mathematica/ref/ComplexityFunction.html
Regards,
--Jean-Marc
Prev by Date:
**Re: opacity "bleeds" in V7 graphics? [compared to V6]**
Next by Date:
**Re: Simplify problem**
Previous by thread:
**Re: Simplify problem**
Next by thread:
**accessing data in a large file**
| |