converting vector result into matrices for surf command
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Hello,in a program there is feald on aplane shown bellow.
the field data was exports and i am trying to recreate this fiels in matlab.
I have a problem where the exported tablable is show in the attached file ,the resulthas a vector as a result.
in surf command i needthe IMAGEEy result be a matrix
its folding every 24 members.
how can i recreate the photo of the progrm thanks?
I tried the photo shown bellow and it gave me gibrish
rows=(with.zmm==48.394400000000000);
data=with(rows,:);
x=data.xmm(1:24);
y=data.ymm;
y2=y(1:24:240);
z=reshape(data.EyImVm,24,[]);
[yy,xx]=meshgrid(x,y2)
surf(xx',yy',z)
Answers (2)
filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/1200898/with.txt';
with = readtable(filename);
with.Properties.VariableNames = {'xmm', 'ymm', 'zmm', 'ExReVm', 'ExImVm', 'EyReVm', 'EyImVm', 'EzReVm', 'EzImVm'};
rows = ismembertol(with.zmm,48.394400000000000);
data = with(rows,:);
x = data.xmm(1:24);
y = data.ymm;
y2 = y(1:24:240);
z = reshape(data.EyImVm,24,[]);
[yy, xx] = meshgrid(x, y2);
surf(xx',yy',z)
xlabel('x'); ylabel('y'); zlabel('EyImVm');
I have no idea what you want to plot.
Use the first two column (that correspond to ‘x’ and ‘y’ respectively), the choose whatever other column you want, and use scatter3 to plot them. m There is no need to reshape them.
T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1200898/with.txt')
x = T1{:,1};
y = T1{:,2};
z = T1{:,3};
Eyv = T1{:,6};
figure
scatter3(x, y, z, 10, z, 'filled')
grid on
colormap(turbo)
view(30,20)
figure
scatter3(x, y, Eyv, 10, Eyv, 'filled')
grid on
colormap(turbo)
view(30,20)
Experiment to get the desired result.
.
6 Comments
fima v
on 21 Nov 2022
I am having a problem understanding what you want to do.
Using only the first 24 elements of each vector (corresponding to y=-11.3408) I get these results —
T1 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1200898/with.txt')
x = T1{:,1};
y = T1{:,2};
z = T1{:,3};
Eyv = T1{:,6};
Uy = unique(y)
% Uym = buffer(Uy,10)
ixr = 1:24;
figure
scatter3(x(ixr), y(ixr), z(ixr), 15, z(ixr), 'filled')
grid on
colormap(turbo)
view(30,20)
figure
scatter3(x(ixr), y(ixr), Eyv(ixr), 15, Eyv(ixr), 'filled')
grid on
colormap(turbo)
view(30,20)
Creating a plane from it —
yv = linspace(min(y(ixr))-0.01, max(y(ixr))+0.01, 24).';
[X,Y] = ndgrid(x(ixr), yv);
% NaNs = nnz(isfinite(Eyv(ixr)))
Z = griddata(x(ixr), yv, Eyv(ixr), X, Y)
figure
surf(X, Y, Z)
grid on
I am not geting any decent results from this.
.
Walter Roberson
on 21 Nov 2022
If you have a 3D cuboid of data (not 2D X and Y and corresponding 2D Z), then you can use slice to visualize along arbitrary planes.
This will not work for the 2D/2D/2D gridded case.
If you had non-gridded vectors of X Y Z where the X Y do not happen to all fall along one plane, then you could potentially griddata() or scatteredInterpolant() to create a 3D volume that you could then slice()
Star Strider
on 22 Nov 2022
@Walter Roberson — I'm having a difficult time understanding what is desired here.
Walter Roberson
on 22 Nov 2022
A line, maybe? Constant z and constant y over a source that is a grid of data would still leave open the possibility of a line graph, EyImVm vs x ?
Star Strider
on 22 Nov 2022
Certainly! Although some sort of scatter plot is at the base of this. The surface — if one exists — evolves from that. I just don’t understand how to get there from the provided data.
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on 22 Nov 2022
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