Re: Parse results from Solve
- To: mathgroup at smc.vnet.net
- Subject: [mg73919] Re: Parse results from Solve
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Sat, 3 Mar 2007 01:01:30 -0500 (EST)
- Organization: The Open University, Milton Keynes, UK
- References: <es916i$2u2$1@smc.vnet.net>
nikki_74 wrote:
> I have used the Solve command to get the solutions for a system of equations. However I want to use these solutions in other commands, such as Reduce and Simplify.
>
> For instance, say the output of Solve is,
> sols= {{x->0,y->0},{x->1,y->2}}
>
> and I want all solutions where x!=y , or , all solutions where y>1.
>
> Can anybody help with this? Thanks!
>
You could use the Cases function as in the following.
In[1]:=
sols = {{x -> 0, y -> 0}, {x -> 1, y -> 2}}
Out[1]=
{{x -> 0, y -> 0}, {x -> 1, y -> 2}}
In[2]:=
Cases[sols, {rx_, ry_} /; (x /. rx) != (y /. ry)]
Out[2]=
{{x -> 1, y -> 2}}
In[3]:=
Cases[sols, {rx_, ry_} /; (y /. ry) > 1]
Out[3]=
{{x -> 1, y -> 2}}
Regards,
Jean-Marc