Re: Get list of function variables?
- To: mathgroup at smc.vnet.net
- Subject: [mg84162] Re: Get list of function variables?
- From: Jason Quinn <jason.lee.quinn at gmail.com>
- Date: Wed, 12 Dec 2007 01:18:41 -0500 (EST)
- References: <fhjs5v$4t3$1@smc.vnet.net> <fhu7j5$7b1$1@smc.vnet.net>
On Dec 9, 6:33 am, Szabolcs Horv=E1t <szhor... at gmail.com> wrote:
> error[expr_, vars_List, errs_List] := Sqrt[D[expr, {vars}]^2 . errs^2]
>
> Use it in the following way:
>
> error[w x y z, {x, y, z}, {ex, ey, ez}]
>
> or
>
> error[f[w, x, y, z], {x, y, z}, {ex, ey, ez}]
>
> Here it is made very clear which symbols represent the function
> variables (x, y, and z), which are simply parameters (w), and which are
> the errors (ex, ey, and ez). And the user of the function has the
> freedom to choose these names.
Very nice solutions, Szabolcs. Thank you very much.