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Bill Simpson
03/26/12 4:06pm

If your actual problem has many, but equally simple, pieces then this might work for you.

In[1]:= y[x_]=Piecewise[{{x-1,-2<=x<0},{x+1,0<=x<2}}];

In[2]:= x[y_]=Piecewise[Map[{Last[#[[2]]],#[[1]]}&, List@@List@@@Reduce[y[x]==a && a∈Reals && -2<x<2,x]]/.a->y];

Now test this by inspection of

In[3]:= Plot[y[x],{x,-2,2}]

In[4]:= Plot[x[y],{y,-3,3}]

What that does is take apart your Piecewise, use Reduce to find each of the inverses and then put those back together to create a new Piecewise.

If your pieces are more complicated then I am concerned that this may not work and may not give you warnings when it doesn't.

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Subject (listing for 'Piecewise')
Author Date Posted
Piecewise Sinval Santos 03/23/12 06:26am
Re: Piecewise Bill Simpson 03/26/12 4:06pm
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