Re: Question about changing variables in PDEs
- To: mathgroup at yoda.physics.unc.edu
- Subject: Re: Question about changing variables in PDEs
- From: withoff
- Date: Sat, 31 Oct 92 10:13:23 CST
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> I have a system of PDE's in in three dependent and two independent
> variables. For example:
> { Dt[f,x] + f Dt[g,t] - f g,
Dt[f,x,t] - Dt[h,x]^2,
Dt[g,x] + Dt[h,t]}
> In[1]:= d = Dt[f,x] + Dt[g,x]
> Out[1]= Dt[f, x] + Dt[g, x]
> In[2]:= d /. Dt[y_,x] -> Dt[y,r]
> Out[2]= Dt[f, x] + Dt[g, x]
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Try using Literal:
In[6]:= d = Dt[f,x] + Dt[g,x]
Out[6]= Dt[f, x] + Dt[g, x]
In[7]:= d /. Literal[Dt[y_,x]] -> Dt[y,r]
Out[7]= Dt[f, r] + Dt[g, r]
Dave Withoff
withoff at wri.com