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Re: Parse results from Solve


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


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