edge colordata property attempts to set are inconsistent

Question

Jeff 2016-7-15

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/295898-edge-colordata-property-attempts-to-set-are-inconsistent

评论： Walter Roberson 2016-7-15

The following section of code works fine when I manually enter them one at a time on the command line, or run the m file with a stop at the set line, and then step past the line.

It doesn't work however if I simply let the m file run completely with a pause. What am I doing wrong?

figure('Position',[166 325 1205 755])
h = plot(gps(:,1),gps(:,2),'r');
spd = a(spdChan).Data(ind);
cmap = colormap;
cmapX = [min(spd):(max(spd) - min(spd))/(size(cmap,1)-1):max(spd)]';
tmp = interp1(cmapX,cmap,spd);
interpCmap = cast([255*tmp 255*ones(size(tmp,1),1)]','uint8');
set(h.Edge, 'ColorType','truecoloralpha', 'ColorBinding','interpolated', 'ColorData', interpCmap);

5 个评论
显示 3更早的评论隐藏 3更早的评论

Jeff 2016-7-15

编辑：Jeff 2016-7-15

在 MATLAB Online 中打开

As a follow up, I notice the size of the Edge.VertexData matrix no longer has a one to one correspondence with the number of data points in the plot. This seems to happen somewhere above 20,000 data points. I assume there is some function that reduces the number of line segments for efficiency. My issue is this produces an error when I create a ColorData matrix the size of the points used to create the plot, and then attempt to set the ColorData property. How can I reconcile this?

h = plot([0:.001:40],[0:.001:20 19.999:-.001:0])
h = 
    Line with properties:
                Color: [0 0.4470 0.7410]
            LineStyle: '-'
            LineWidth: 0.5000
               Marker: 'none'
           MarkerSize: 6
      MarkerFaceColor: 'none'
                XData: [1x40001 double]
                YData: [1x40001 double]
                ZData: [1x0 double]
    Show all properties
>> h.Edge.get
          AlignVertexCenters: 'off'
             AmbientStrength: 0.3000
                ColorBinding: 'object'
                   ColorData: [4x1 uint8]
                   ColorType: 'truecolor'
             DiffuseStrength: 0.6000
            HandleVisibility: 'off'
                     HitTest: 'off'
                       Layer: 'middle'
                     LineCap: 'none'
                    LineJoin: 'round'
                   LineStyle: 'solid'
                   LineWidth: 0.5000
               NormalBinding: 'none'
                  NormalData: []
                      Parent: [1x1 Line]
               PickableParts: 'visible'
    SpecularColorReflectance: 1
            SpecularExponent: 10
            SpecularStrength: 0.9000
                   StripData: [1 7474]
                     Texture: [0x0 GraphicsPlaceholder]
                  VertexData: [3x7473 single]
               VertexIndices: []
                     Visible: 'on'
       WideLineRenderingHint: 'software'

Jeff 2016-7-15

I'm running 2015b

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Kelly Kearney 2016-7-15

2
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/295898-edge-colordata-property-attempts-to-set-are-inconsistent#answer_228801

在 MATLAB Online 中打开

I've found that messing around with some of the undocumented properties of new graphics objects can be finicky, with properties resetting to their original values later, or failing to change when run in a script (as you're seeing). I recommend only resorting to this sort of hacking when you can't find any workarounds using the documented properties.

Luckily, there's an easy workaround for color-changing lines, and it eliminates the need to do the color interpolation manually: use a patch instead.

x = [0:.01:20];
y = [0:.01:10 9.99:-.01:0];
hln = patch([x NaN], [y NaN], [y NaN]);
set(hln, 'edgecolor', 'interp');

2 个评论
显示无隐藏无

Jeff 2016-7-15

编辑：Jeff 2016-7-15

Thanks, I hadn't thought of that. I was also planning on using transparency as a crude 4th dimension. I'll have to research this more to see if I can also control that as well?