In article <MPG.162ed391d0e34c3c989704@news.frii.com>,
David Fanning <david@dfanning.com> wrote:
> jiali (jiali3@21cn.com) writes:
>
>> I wonder how to add another axis. First create a frequency-power plot:
>>
>> plot,fre,power,xrange=[1,10],yrange=[0,10],xtitle='Frequency '
>>
>> I hope to add an axis on the top but with period(=1/frequency) ticks. Maybe
>> like following:
>>
>> aixs,1,10,/xaxis,xrange=[1,0.1], xtitle='Period',......???
>>
>> Would you please help me to finish the above?
>
> Well, it will be something like this:
>
> plot,fre,power,xrange=[1,10],yrange=[0,10], $
> xtitle='Frequency', xstyle=8, $
> position=[0.15, 0.15, 0.95, 0.85]
> axis, xaxis=1, xrange=[1,0.1], xtitle='Period', /save
Awww! This is too easy! It does help that 1.0 lines up with 0.1, 2.0 with
0.2, ... etc. Things look nice. How about when you want to have
xrange = [0,15], but you want the upper axis to be some specific values
that are calculated from the lower axis. I run into this typically in
trying to have two different ways of specifying the same underlying
variable. For a no so moronic example, let the x axis be some length
in metres. Now, for some people's benefit, I would like to have
feet on the upper scale. But, it is ugly to have 1.5432, 2.1793, ...
labels. One would like that hash marks to be laid at 1.5, 2.0, etc.
Any chance of a routine out there?
thanks
--
Surendar Jeyadev jeyadev@wrc.xerox.com
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