Re: DSolve bug
- To: mathgroup at smc.vnet.net
- Subject: [mg97808] Re: DSolve bug
- From: "Sjoerd C. de Vries" <sjoerd.c.devries at gmail.com>
- Date: Sun, 22 Mar 2009 05:48:18 -0500 (EST)
- References: <gq2ep1$e8g$1@smc.vnet.net>
Hi Sotirios,
Why do you think it's a bug. C[1][z][x] is a perfectly legitimite way
to type a function of two variables. Look here:
In[64]:= f[x_][y_][z_] := x^y^z
In[65]:= f[a][b][c]
Out[65]= a^b^c
Checking the solution:
In[63]:= D[C[1][z][x] + C[2][z][y], x, y]
Out[63]= 0
No problemo.
Cheers -- Sjoerd
On Mar 21, 12:16 pm, Sotirios Bonanos <sbon... at inp.demokritos.gr>
wrote:
> Hello,
>
> I have encountered the following bug in DSolve:
>
> DSolve[D[F[x, y, z], x, y] == 0, F[x, y, z], {x, y, z}]
>
> gives {{F[x, y, z] -> C[1][z][x] + C[2][z][y]}}
>
> instead of {{F[x, y, z] -> C[1][x, z] + C[2][y, z]}}
>
> I don't know if this has been fixed in Mathematica 7, but it is present i=
n versions 5 and 6.
>
> S. Bonanoshttp://www.inp.demokritos.gr/~sbonano/