Re: [Gnuplot-info] Plotting parameters as data points

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

Stemat <stefan.materne <at> physik.tu-muenchen.de> writes:

> 
> 
> Hello everybody! 
> I have the following problem:
> After a series of fits I want to summarize my fit results in a seperate plot
> with every result of the parameter of the various fits depicted as a point.
> Say my parameters are named a1....a7 for the fits I have (all have only one
> parameter of interest)
> I tried the following:
> 
> plot '-' w p ls 2 
> 1 a1 
> 2 a2  
> 3 a3  
> 4 a4  
> 5 a5  
> 6 a6  
> 7 a7
> e
> 
> However, gnuplot just plots the points (0,1),
> (1,2),(2,3),(3,4),(4,5),(5,6),(6,7)
> 
> If I explicetly write 
> 
> plot '-' using 1:2 w p ls 2 
> 1 a1 
> 2 a2  
> 3 a3  
> 4 a4  
> 5 a5  
> 6 a6  
> 7 a7
> e
> 
> it says ' Skipping data file with no valid points'
> The same happens if i don't try to draw my fitparameters, but explicetly set
> the parameters befor, e.g. a1=3, a2=2, a3 =0,...
> 
> So basically the questions: how do I plot parameters as data points?
> 
> As a workaround I could also print the results into a table file and load
> this again. How do I do that?
> Using the logfile of the fit is not an option for me as there is too much
> additional information which I would have to delete manually.
> 
> I am using gnuplot 4.4 patchlevel 4 on a windows system.
> 
> Thank you for your help!

you can't plot the contents of variables by reading the variable
names from a file inside a plot command.
when reading from a file, the plot command expects numbers.

you may write the fit parameters to a file after each individual
fit and plot the data inside this file later.

before the first fit open a file to print the fit parameters into with

set print "some_filename"

after each fit, save the fit parameters (e.g. a and b) with

print a, b

after the fits are done you have a data file containing all the fit
parameters which you may plot

plot "some_filename" using 0:1