[R] numeric derivation

Gabor Grothendieck
Sun, 12 Oct 2008 14:34:56 -0000

?deltat

On Sun, Oct 12, 2008 at 9:45 AM, Oliver Bandel
<oliver at first.in-berlin.de> wrote:
> Zitat von Gabor Grothendieck <ggrothendieck at gmail.com>:
>
>> If you simply want successive differences use diff:
>>
>> x <- seq(4)^2
>> diff(x)
>>
>> tx <- ts(x)
>> diff(tx)
> [...]
>
> Oh, cool, thanks.
>
> But what about  diff / delta_t ?
>
> Do I have to calculate it by my own, or is there
> already a function for making a difference-qoutient?
>
> This would be fine to have, because for example
> coming from space vs. time to velocity vs. time
> and acceleration vs. time (and further derivatives)
> are also a time-series.
>
> The possibility of using the advantages of the time series class here,
> would be fine.
>
>
> Ciao,
>   Oliver
>