[R] a symbolic derivative question, please

[Richard M. Heiberger]

`[` is a function.  So the deriv program is seeing

`[`(y,3)*r1 + r2

> letters[5]
[1] "e"
> `[`(letters, 5)
[1] "e"

On Fri, Jan 9, 2015 at 12:31 PM, Erin Hodgess <erinm.hodgess at gmail.com> wrote:
> Hello!
>
> I have the following:
>
> zzz <- expression(y[3]*r1 + r2)
> deriv(zzz,c("r1","r2"))
> Error in deriv.default(zzz,c("r1","r2")) :
>    Function '`[`' is not in the derivatives table
>
> What am I missing, please?  Since y is not one of the variables that is
> being "acted upon", why is the [] an issue, please?
>
> Thank you for any help!
>
> Sincerely,
> Erin
>
>
> --
> Erin Hodgess
> Associate Professor
> Department of Mathematical and Statistics
> University of Houston - Downtown
> mailto: erinm.hodgess at gmail.com
>
>         [[alternative HTML version deleted]]
>
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