gnuplot-info

[Gnuplot-info] trouble protting timediff

[walter h. <wh...@bf...>]

hi list,
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: yes i can preprocess that file and use seconds in the first place
      but i would like to understand what is going on here

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

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

Re: [Gnuplot-info] trouble protting timediff

[walter h. <wh...@bf...>]

Am 21.01.2014 12:43, schrieb Thomas Sefzick:
> 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
> 
> 


works much better,
That should  be mentioned in time/date help !

re,
 wh