#285 Color Column Not Grided

open
nobody
None
5
2014-08-21
2011-03-06
Douglas
No

I have some data that isn't gridded. The gridding functions in gnuplot are spectacular! But one thing confuses me: when I put in the commands at the end of this request, I receive the error: "Gridding of the color column is not implemented"

I would understand why gnuplot can't interpolate between an rgb triplet, but this is a paletted color scheme. Am I failing to make an appropriate setting somewhere?

set palette model HSV functions gray,1,1
set cbrange[-pi:pi]
set hidden3d
set pm3d implicit at bs
a = 2.4600e-10
i = {0.0,1.0}
scale = .02
limit = 6 #in normal point size, so one or five are good numbers
unset xtics
unset ytics
unset ztics
unset border
set dgrid3d 100,100,100 splines
set cbtics ( "-{/Symbol p}" -pi, "-{/Symbol p}/2" -pi/2.0, "0" 0, "{/Symbol p}/2" pi/2.0, "{/Symbol p}" pi)

set title "Resonant State Wavefunction"

radius(z) = abs(z)*scale
splot '-' u 1:2:(radius($3+$4*i)):(arg($3+$4*i)) w pm3d notitle

Discussion

  • Douglas
    Douglas
    2011-03-06

    Similarly the problem arises for the command:

    splot '-' u 1:2:(radius($3+$4*i)):(arg($3+$4*i)) w p pt 7 ps 1 lc palette notitle

     
  • Douglas
    Douglas
    2011-03-07

    Any interest in this problem? I figure a palette color is a linear function just like height and should be easy to implement.

     
  • Douglas
    Douglas
    2011-03-09

    Here's a solution to the problem. I still think this could be accounted for by gridding the color column, and I may move this to a feature request:

    set palette model HSV functions gray,1,1
    set cbrange[-pi:pi]
    set hidden3d
    set pm3d at bs
    set dgrid3d 200,200 splines
    a = 2.4600e-10
    i = {0.0,1.0}
    scale = .02
    limit = 6 #in normal point size, so one or five are good numbers
    unset xtics
    unset ytics
    unset ztics
    unset border
    set cbtics ( "-{/Symbol p}" -pi, "-{/Symbol p}/2" -pi/2.0, "0" 0, "{/Symbol p}/2" pi/2.0, "{/Symbol p}" pi)

    set title "Resonant State Wavefunction"

    radius(z) = abs(z)*scale
    #:(arg($3+$4*i))

    set table 'tmp.dat'
    splot '-' u 1:2:(radius($3+$4*i)) w linesp pt 7 ps 1 lc palette notitle
    data
    unset table

    set table 'tmp2.dat'
    splot '-' u 1:2:(arg($3+$4*i)) w linesp pt 7 ps 1 lc palette notitle
    data
    unset table

    unset dgrid3d
    splot '< paste tmp.dat tmp2.dat' u 1:2:3:7 w pm3d notitle

     
  • This is asking for a feature that gnuplot currently simply doesn't have. It would call for gnuplot to run the gridding algorithm twice: once for the z column, and again for the 'colour' column.

    Thus the error message you got, and the reason to move this to Feature Requests.

     
  • Joachim Seibt
    Joachim Seibt
    2012-10-01

    Hello,

    My current problem seems to be similar.
    I also have a data set of amplitude and phase values on a two-dimensional grid
    and would like to display them using a gnuplot script.
    Thereby the phase is aimed to be represented by a hue parameter, whereas the amplitude
    determines the color intensity.
    Is the solution which was suggested here appropriate for this issue?
    I tried to use the given code, but there seem to be difficulties with the interpolation.
    Can you tell me how to proceed?

    Best regards,

    Joachim