piece-wise-linear scale

[Daniel J S. <dan...@ie...>]

em...@ru... wrote:

>... +----------+----------+----------+----------+----------+----------+ ...
>   2800        2400       2000       1800       1600       1400       1200
>
>
>
>   set irscale
>
>Do you think this might be worth adding?  If so, can you think of a better
>way to implement it, from the user's point of view?  I'd like to have some
>expert opinions before I start messing around too much.  Just now someone tells
>me there's a simple way to do this already ;)
>

This can be done by passing the x data through a nonlinear function, and 
then manually altering the x-tics so they reflect the numbers accurate, 
for example as you've given above.  (The supplying of the tics is the 
tedious part... and you *must* always make sure that the tics break 
right at a location where the nonlinear scaling changes... otherwise 
there is no meaningful way to interpret the data)  As an example, try 
the following:

plot 'battery.dat' using 1:2

vs.

plot 'battery.dat' using ((($1)<=20)*($1) + (($1)>20)*(($1-20)*0.5 
)):2+20)):2

Of course, this is very tedious.  But those who are accomplished with 
the awk scripts in gnuplot might be able to suggest if this can be made 
easy.

I think "irscale" is too specific to be of use in gnuplot.  However, a 
more generalized description or name of what you are suggesting might be 
"piece-wise-linear" scales.

Dan