Re: Peculiar output from DSolve
- To: mathgroup at smc.vnet.net
- Subject: [mg37015] Re: [mg36994] Peculiar output from DSolve
- From: Selwyn Hollis <selwynh at earthlink.net>
- Date: Sun, 6 Oct 2002 05:33:16 -0400 (EDT)
- References: <d7.1e734c25.2acec78b@aol.com>
- Sender: owner-wri-mathgroup at wolfram.com
I'm only a little embarassed for not having realized what was happening.
(Perhaps I should have slept on it.)
Surely I'm not alone in thinking this symbolism is highly nonintuitive.
But of course, for it to be otherwise would require another protected
symbol...
---
Selwyn
BobHanlon at aol.com wrote:
> In a message dated 10/4/2002 5:13:02 AM, selwynh at earthlink.net writes:
>
>
>>In: DSolve[y*D[u[x, y],x] == x*D[u[x, y],y], u[x,y], {x, y}]
>>
>>Out: {{u[x, y] -> C[1][(1/2)*(x^2 + y^2)]}}
>>
>>Square brackets are used as grouping symbols in the result!?? :^O
>>
>>Somebody say it isn't so.
>>
>
>
> "It isn't so"
>
> The square bracket is not delineating a factor it is enclosing the argument
> to an arbitrary function named C[1]. While the function is dependent on both
> x and y the dependence only occurs in the combination (x^2+y^2).
>
>
> Bob Hanlon
>