Re: Q: Symbolic manipulation with Mathematica
- Subject: [mg3034] Re: Q: Symbolic manipulation with Mathematica
- From: BobHanlon at aol.com
- Date: 25 Jan 1996 05:41:19 -0600
- Approved: usenet@wri.com
- Distribution: local
- Newsgroups: wri.mathgroup
- Organization: Wolfram Research, Inc.
- Sender: mj at wri.com
In[1]:= g[func_] := func + x D[func, x]; In[2]:= g[f[x]] Out[2]= f[x] + x f'[x] In[3]:= g[f[x, y]] Out[3]= (0,1) x f [x, -] x e (1,0) x f[x, -] + x (------------ + f [x, -]) e e e In[4]:= y = x/e; g[f[x, y]] Out[5]= (0,1) x f [x, -] x e (1,0) x f[x, -] + x (------------ + f [x, -]) e e e In[6]:= Clear[y]; g[f[x, y /. y -> x/e]] /. x/e -> y Out[7]= (0,1) f [x, y] (1,0) f[x, y] + x (------------ + f [x, y]) e Bob Hanlon bobhanlon at aol.com > Newsgroups: sci.math.symbolic > From: sergio at sci.ccny.cuny.edu (Sergio Rojas) To: mathgroup at smc.vnet.net > Subject: Q: Symbolic manipulation with Mathematica > Date: Sun, 21 Jan 1996 21:33:57 GMT > > Hi fellows, > > I would like to know whether is possible to do the > following with Mathematica: > > In[15]:= test = f[x] + x*D[f[x],x] > > Out[15]= f[x] + x f'[x] > > In[16]:= test /. f[x]->f[x,y] > > Out[16]= f[x, y] + x f'[x] > > However, I would like to get something like: > > f[x,y] + x*D[f[x,y],x] > > which then Mathematica can write in the form: > > (1,0) > Out[17]= f[x, y] + x f [x, y] > > Other manipulation I am trying to do is as follows: > > In[18]:= y = x/e > > x > Out[18]= - > e > > In[19]:= test = f[x,y] + x*D[f[x,y],x] > > (0,1) x > f [x, -] > x e (1,0) x > Out[19]= f[x, -] + x (------------ + f [x, -]) > e e e > > If there any way to get this equation in the form: > > (0,1) > f [x, y] (1,0) > f[x, y] + x (------------ + f [x, y]) > e > > d f[x,y] (1,0) >Finally, is any way to use the notation: -- instead of f [x,y] > dx > I'll appreciate any suggestion. > > rojas > > E-mail: sergio at scisun.sci.ccny.cuny.edu