Re: [Gnuplot-info] plot by filtering some lines

[William Xu <wil...@gm...>]

Hans-Bernhard Bröker <HBB...@t-...> writes:

>> which should do the same as: 
>>>> ,----
>>>> | plot 'result.log' using ($4 == 1 $3 : 1/0):5 title '1 session' with linespoints
>>>> `----
>> 
>> right?
>
> No.  Data that's not there at all (because 'awk' ate it) is not quite 
> the same as data with infinite or undefined coordinates.

Oh, so you mean that in ($4 == 1 ? $3 : 1/0):5, when $4 != 1, even
(1/0):5 is a valid coordinate? I was thinking that it could be simply
ignored by plot.

I was following this from the manual: 

,----[ http://www.gnuplot.info/docs/node133.html ]
| One trick is to use the ternary ?: operator to filter data:
| 
| 
|      plot 'file' using 1:($3>10 ? $2 : 1/0)
| 
| 
| which plots the datum in column two against that in column one provided
| the datum in column three exceeds ten. 1/0 is undefined; gnuplot quietly
| ignores undefined points, so unsuitable points are suppressed. 
`----

-- 
William