Re: wxt mouse scrolling anomalies

[<pl...@pi...>]

On 11/09/12 18:17, sfeam (Ethan Merritt) wrote:
> On Friday, 09 November 2012, pl...@pi... wrote:
>> Hi ,
>>
>> recent cvs gnuplot:
>>
>> I've just noticed that mouse scrolling window in wxt  causes functions
>> to be replotted full width , not with in the limits of data as in
>> initial plot.
>>
>> Also grid gets calculated to grossly different tic intervals on just one
>> scroll event in either direction. eg my plot auto scales to [-1:+1] and
>> gets 0.2 intervals. Or scroll it gets 0.5 intervals.
>>
>> Autoscale button fixes it , replot button/command, no.
>
> I am not seeing any of that here.
> So I really can't say what might be going wrong.

OK, I'll try to create a minimalistic test case that reproduces the problem.

>
>> I would have expected scroll to do no more that move what is already
>> there.
>
> Well no, that's not how it works.  If it did that it would show blank
> space in the area that enters your field of view.  Instead it adds some
> incremental amount to the upper/lower axis range and replots.
> I can see how there may be certain cases for which that could change
> the tic interval, but I haven't noticed it being a problem in practice.

Yes, obviously blank area has to be filled. I meant that the 
presentation of the data would remain the same ie the grid does not get 
recalibrated and funtions don't start getting rendered with different 
end points.

>
>> I don't recall seeing either of these before (though the function
>> range may not always be obvious).  Previously running prob 6m old CVS.
>
> I don't see anything much related to scrolling in the ChangeLog
> for the last 6 months.
> What "last modified" date is reported when you start the program?

         G N U P L O T
         Version 4.7 patchlevel 0    last modified 2012-10-16
         Build System: Linux i686

>
>> datafile has data in range [-50:50] which autoscales to [-60:60]
>>
>> f(x)=0
>> plot datafile, f(x)
>
> I tried that.  Nothing special happened with regard to scrolling.
>

Actually,I'm getting some very odd things happening here.

Firstly , being still half asleep it typed in some data with commas and 
did not get what I intended (so not bug yet)

gnuplot> f(x)=0
gnuplot> plot "-" w l , f(x)
input data ('e' ends) > -50,1
input data ('e' ends) > 0, 1
input data ('e' ends) > 50, -1
input data ('e' ends) > e

         set xrange [ 0.00000 : 2.00000 ] noreverse nowriteback
         set yrange [ -60.0000 : 60.0000 ] noreverse nowriteback


Then I entered what I intended.

gnuplot> plot "-" w l , f(x)
input data ('e' ends) > -50 -1
input data ('e' ends) > 0 1
input data ('e' ends) > 50 -1
input data ('e' ends) > e


However , this did not rescale, I got what appeared to be two flat lines 
with the ranges still as shown above.

Then I hit the autoscale button (wxt) and got my triangular data line 
but the function f(x) was only plotted over its previous x extent of 0:2 
  and was I tiny segment on the now correct ranges:


         set xrange [ * : * ] noreverse nowriteback  # (currently 
[-60.0000:60.0000] )
         set yrange [ * : * ] noreverse nowriteback  # (currently 
[-1.00000:1.00000] )

No amount of replot, rescale etc seems to correct this, so there is a 
difference of behaviour here for in line data rather than a file. (Can't 
re-read pipe I guess).

Now if I put the same data in a text file I can reproduce what I 
originally reported:

gnuplot> !cat "fx_test.dat"
-50 -1
0 1
50 -1

  plot "fx_test.dat" w l , f(x)


That test case plots the function to the width of the data on initial 
display and on autoscale button but any scroll event will cause the 
function to be plotted full with of x axis.

So it seems that  scolling , which implies setting an explicit range 
instead of auto, changes the way the function limits are determined.

regards, Peter.