[rrd-users] rpn question

Alex van den Bogaerdt alex at ergens.op.het.net
Sun May 11 00:07:42 CEST 2008

On Sat, May 10, 2008 at 05:53:57PM -0400, R Dicaire wrote:
> On Sat, May 10, 2008 at 5:39 PM, Alex van den Bogaerdt
> <alex at ergens.op.het.net> wrote:
> > You _are_ dividing all values above 20000 by 10.  But it seems to
> > me you want to divide only the portion above 20000 by 10 and add
> > this to 20000.
> >
> > 1:  Why ?
> The rest of the data this particular graph displays doesnt vary much,
> so when apache_bytes gets to a certain point, the other data isn't
> very legible.

Have you looked at a logarithmic scale ? It may be something you
could use.

> > if (x>20000) then return (x-20000)/10+20000
> > else return x
> Thank you, I'll try and figure this out.

if x>20000 then:             x,20000,IF
return (x-20000)/10+20000:   x,20000,-,10,/,20000,+
else return x:               x

concatenate:  CDEF:y=x,20000,IF,x,20000,-,10,/,20000,+,x

you substitute names for x and y.

Also: it is late, it's warm, I'm tired and I did not verify that
this does indeed produce what you need.  So:  debug!

Alternatively: if you are not interested in anything above 20000,
why not set an upper limit of 20000 and set option rigid ?

Alex van den Bogaerdt

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