[rrd-developers] Unexpected behaviour of PREDICT and PREDICTSIGMA

[Tobias Oetiker]

Hi Steve,

Today Steve Shipway wrote:

> So, assuming stptr is zero based, this means my `analysis of the
> behaviour of negative shift counts is correct.
>
> My question, though, is more to ask if this was intended by
> design, or if it is a 'feature'?
>
> Intuitively, I would have expected this:
>
> CDEF:y=s,-n,x,PREDICT
>
> to result in shifts of s, 2s, 3s, .... ns
>
> However, it actually results in shifts of 0, s, 2s, ... (n-1)s
>
> Either way, it can't be changed now as it would potentially alter
> existing behaviour...

I don't know if the original author intended this. But now that you
analyzed it, how could I entice you to write a few lines for the
manual page ?

cheers
tobi


> Steve
>
> Steve Shipway
> University of Auckland ITS
> UNIX Systems Design Lead
> s.shipway at auckland.ac.nz
> Ph: +64 9 373 7599 ext 86487
>
>
>

-- 
Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland
www.oetiker.ch tobi at oetiker.ch +41 62 775 9902