Re: multiple plot lines with plot '-'

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

On 05/16/12 18:35, Daniel J Sebald wrote:
> However, this isn't as different as you think.  I would guess that if
> "datafile" were changed at an instant between when gnuplot does the two
> plots, the two plots would look different.  The analogy is typing the
> same thing at the keyboard or pipe when using '-'.
>
> Perhaps there should be a mode switch, "use the same data" or "don't
> reread".  But I'm not sure how crucial that is.

This is not so hypothetical and improbably as it may seem.

Some of my embedded plots take 16-20s to run the ARM hardware I'm using. 
It is totally possible (maybe probable) that the source file could 
change in that time.

Since the time between the first plot and the second one is a fairly 
arbitrary one, depending up on the hardware and the length of data , I 
can't see it being a useful feature.  Maybe someone else can.

The trivial case I gave was intentionally simplistic. Consider this 
variation:

plot datafile using 1:2 , '' using 1:3

Now both these lines are coming out on the same plot , I would expect it 
to be a snapshot of the data at the same point in time. We are almost 
certainly going to be comparing them. Currently there is a possibility 
that the two lines represent different states of the data set.  If they 
were not coincident in time it could lead to misrepresentation or 
misinterpretation.

I would consider it a defect.

Peter.