question regarding ploting a table as a surface

Hello, i have the following EM field shown bellow, i have extracted the field into a table attached as zipped txt and a printscreen shown bellow.

i have only one value for each (x,z) coordinate how do i recreate this plot in matlab?

Thanks.

data=readtable('export.txt');
data_vec=data(:,4);
d_y_arr=table2array(data_vec);
mat_data=reshape(d_y_arr,[230,230]);
z_vec=table2array(data(1:230,3));%taking the repetative 230 values of z vector
x_vec=table2array(data(1:230:end,1));%take every 230 member for vector of x
[xx,zz]=meshgrid(x_vec,z_vec);
h=surf(xx,zz,mat_data)
set(h,'linestyle','none');

Answer 1

[Voss]

You can use the four-input syntax for surf (X,Y,Z,C), and set the Y to zeros.

unzip('export.zip')
data=readtable('export.txt')

data = 52900×9 table
     Var1     Var2    Var3        Var4        Var5         Var6          Var7          Var8          Var9   
    ______    ____    _____    __________    _______    __________    __________    __________    __________

    -13.45     0      -7.45    -0.0054221     1.0022     0.0001463    0.00027693    0.00032724    -0.0032107
    -13.45     0      -7.35      0.015197    0.99913     0.0001455     0.0002827    0.00034654    -0.0032987
    -13.45     0      -7.25      0.035816    0.99607    0.00014469    0.00028847    0.00036585    -0.0033867
    -13.45     0      -7.15      0.056435    0.99302    0.00014388    0.00029424    0.00038515    -0.0034746
    -13.45     0      -7.05      0.077055    0.98996    0.00014308    0.00030001    0.00040446    -0.0035626
    -13.45     0      -6.95      0.097674     0.9869    0.00014227    0.00030577    0.00042376    -0.0036506
    -13.45     0      -6.85       0.11829    0.98385    0.00014147    0.00031154    0.00044307    -0.0037386
    -13.45     0      -6.75       0.13891    0.98079    0.00014066    0.00031731    0.00046237    -0.0038265
    -13.45     0      -6.65       0.15953    0.97774    0.00013985    0.00032308    0.00048168    -0.0039145
    -13.45     0      -6.55       0.18015    0.97468    0.00013905    0.00032885    0.00050098    -0.0040025
    -13.45     0      -6.45       0.20077    0.97162    0.00013824    0.00033462    0.00052028    -0.0040904
    -13.45     0      -6.35       0.22139    0.96857    0.00013744    0.00034038    0.00053959    -0.0041784
    -13.45     0      -6.25       0.24201    0.96551    0.00013663    0.00034615    0.00055889    -0.0042664
    -13.45     0      -6.15       0.26263    0.96245    0.00013582    0.00035192     0.0005782    -0.0043544
    -13.45     0      -6.05       0.28325     0.9594    0.00013502    0.00035769     0.0005975    -0.0044423
    -13.45     0      -5.95       0.30243    0.95169    0.00013413    0.00036394     0.0006249    -0.0045988

N = 230;
mat_data=reshape(data{:,4},[N,N]);
z_vec=data{1:N,3};%taking the repetative 230 values of z vector
x_vec=data{1:N:end,1};%take every 230 member for vector of x
[xx,zz]=meshgrid(x_vec,z_vec);
colormap(jet)
% h=surf(xx,zz,mat_data,'linestyle','none')
h=surf(xx,zeros(N),zz,mat_data,'linestyle','none')

h = 
  Surface with properties:

       EdgeColor: [0 0 0]
       LineStyle: 'none'
       FaceColor: 'flat'
    FaceLighting: 'flat'
       FaceAlpha: 1
           XData: [230×230 double]
           YData: [230×230 double]
           ZData: [230×230 double]
           CData: [230×230 double]

  Show all properties

colorbar
% caxis([0 1]) % if you want the color-limits to be [0,1] as in the picture
box on
xlabel('x')
ylabel('y')
zlabel('z')

Note that you're using the 4th column of data (ExRe), but the 5th column (ExIm) is pointed to in the table screenshot.

Answer 2

[Cris LaPierre]

Depending how exactly you are trying to duplicate the image you shared, it looks like you don't want a surface. You want to use scatter3 or plot3. Another observation is that the markersizse appears to change with the value of V/m.

Not perfect, but here's some code that could get you started.

unzip('export.zip')
data=readtable('export.txt');

sz = rescale(abs(data.Var5),0.1,5);
scatter3(data.Var1,data.Var2,data.Var3,sz,abs(data.Var5),"filled")
colormap jet

c = colorbar;
c.Title.String = 'V/m';
c.Title.FontSize = 14;
c.Title.FontWeight = "bold";

axis off
axis equal
grid off
box on

[Cris LaPierre]

Another thing to note is that, in the shared image, the data displayed in the figure is a subset of the full dataset (I counted 31 rows of data, while the raw dataset has 230).