Re: [Gnuplot-info] trouble protting timediff

[Thomas S. <t.s...@fz...>]

walter harms <wharms <at> bfs.de> writes:

> the idea here was to plot the time difference ($2-$1) vs value (3).
> The results are confusing and i have no idea what the problem may be
> (me or gnuplot).
> the x-axes i see is 0 0 1 1 2 2 3
> but i expected to see the time difference in seconds.
> ...
> note: this is a simplified example
> 
> # from          to     value
>   1990-01     1990-06   27
>   1990-01     1991-12   35
>   1989-12     1992-01   22
> 
> set timefmt "%Y-%m"
> set xdata time
> set format x "%s"   # seconds to illustrate the problem
> plot "test.dat" using ($2-$1):3 with p ps 2 pt 5

"$2" doesn't work for time data, use the "timecolumn(2)"
function instead.

plot "test.dat" using (timecolumn(2)-timecolumn(1)):3 with p ps 2 pt 5

should work