Re: How to use table header as title inside for loops?

[Ethan A M. <merritt@u.washington.edu>]

On Sunday 15 March 2009, James R. Van Zandt wrote:
> 
> Ethan Merritt wrote:
> > On Thursday 12 March 2009, Juergen Wieferink wrote:
> > I have [...] modified the parsing code, which now accepts:
> >     plot ...  title columnheader
> >     plot ...  title columnheader(N)
> > The option is now handled by the normal title parsing code, so there is
> > no strangeness with the order of title options on the command line.
> >
> > The original form of the command, which was never documented but was 
> > used in several of the demos, is now deprecated.  However it still works
> > if you ./configure --enable-backwards-compatibility
> > Thus
> >    plot ... using 1 title 1 
> > should be re-written using any of the following:
> >    plot ... using 1 title col
> >    plot ... using 1 title columnhead(1)
> >    set key autotitle columnhead
> >    plot ... using 1
> 
> Suppose I have data that looks like this:
> 
>    1.000000 2.000000 2.000000
>    2.000000 1.000000 2.000000
>    3.000000 0.666667 2.000000
>    4.000000 0.500000 2.000000
>    
>    
>    1.000000 3.000000 3.000000
>    2.000000 1.500000 3.000000
>    3.000000 1.000000 3.000000
>    4.000000 0.750000 3.000000
>    
>    
>    1.000000 4.000000 4.000000
>    2.000000 2.000000 4.000000
>    3.000000 1.333333 4.000000
>    4.000000 1.000000 4.000000
>    ...
>    
> I would like to plot each datablock with its own title taken from the
> third column.  I can use
> 
>   plot for [n=0:3] 'lab.dat' in n title 3
> 
> except that the first line of each datablock is not plotted. 

Of course it isn't.  You have told the program that the first line
contains labels, not data.

> Maybe what I want is
> 
>   plot for [n=0:3] 'lab.dat' in n title datastring(3)
> 
> but that isn't implemented?

I don't know, because I don't quite understand what you are trying to do.
How can every line of the data file contain a plot title?
I could understand using each 3rd column value as a point symbol,
or a color, or an xticlabel, etc,  but it doesn't make sense to have
multiple titles for the same plot.

Maybe you are over-thinking this?  If that is really what your data file
looks like, maybe you just want

   plot for [n=0:3] 'lab.dat' in n title sprintf("Data block %d",n)

	Ethan

 
> 
> BTW my application is a simulation where several of the columns have
> input parameters, and the rest of the columns have outputs.  I can
> plot one output as a function of two inputs using splot.  However, to
> make it possible to actually read values off the curves, I would like
> to plot iso-<whatever> lines: output as a function of one input
> parameter, for selected values of a second parameter, and all other
> parameters held constant.  It would be very helpful to get the curve
> labels from the data file itself.

Sorry, I still don't follow what you are aiming for.
You are doing something to select  coordinate pairs from a subset of
lines in the file.  OK.  But whatever set you pick within a single "plot"
command can have only one title, right?


>             - Jim Van Zandt
>