3D plot of data

Hello.

I have a data set consisting of stresses accociated with a coordinate point (x,z). The data is attached, note that all the y coordiantes are the same, ie the stresses are on a flat surface consisting of x and z. The data for the stresses are in colum B.

I would like to create a 3D plot or surface of my stresses, but I am unsure how to associate my stresses with a specific point, so that I can plot them. I have tried using meshgrid and surf, but not with any kind of sucess worth attaching.

Answer 1

[KSSV]

Option 1: USe scatter:

[num,txt,raw] = xlsread('Data_3Dplot.xlsx') ;
num = num(9:end,:) ; 

nodes = num(:,1) ; 
value = num(:,2) ; 
x = num(:,3) ; 
y = num(:,4) ; 
z = num(:,5) ; 
scatter3(x,y,z,10,value,'filled')

Option 2: Make unstructured grid

[num,txt,raw] = xlsread('Data_3Dplot.xlsx') ;
num = num(10:end,:) ; 

nodes = num(:,1) ; 
value = num(:,2) ; 
x = num(:,3) ; 
y = num(:,4) ; 
z = num(:,5) ; 


dt = delaunayTriangulation(x,z) ;
t = dt.ConnectivityList ; 
p = dt.Points ; 
p(:,3) = value ; 
trisurf(t,p(:,1),p(:,2),p(:,3));
view(2)
shading interp ; colorbar

Option 3: Make a structured grid

[num,txt,raw] = xlsread('Data_3Dplot.xlsx') ;
num = num(10:end,:) ; 

nodes = num(:,1) ; 
value = num(:,2) ; 
x = num(:,3) ; 
y = num(:,4) ; 
z = num(:,5) ; 

N = 500 ; 
xi = linspace(min(x),max(x),N) ; 
zi = linspace(min(z),max(z),N) ; 
[X,Z] = meshgrid(xi,zi) ; 
C = griddata(x,z,value,X,Z) ; 

surf(X,Z,C) 
shading interp ; colorbar 
view(2)

[Malthe Gissel]

Hello

Thank you very much for taking the time to come up with all these suggestions, I greatly appreciate that! While this is not exactly what I had in mind, it definitly pushed me in the right direction.

I really like option 1, but while it obviously is a 3 dimensional coordinate system, is there any way to not use the y coordinates, and then display the stresses as a height above the plane made of x and z corrdintes?

Once again, thank you very much for your help and the quick response.

[KSSV]

That option is already there in the solution.

[num,txt,raw] = xlsread('Data_3Dplot.xlsx') ;
num = num(10:end,:) ; 

nodes = num(:,1) ; 
value = num(:,2) ; 
x = num(:,3) ; 
y = num(:,4) ; 
z = num(:,5) ; 
scatter(x,z,10,value,'filled')
colorbar

Thanks is accepting the answer. :)

[Malthe Gissel]

I dont mean to be rude, and I´m sorry if I have been unclear, but it does not solve my problem. As you can see, on the attached photos, the stress plot is a 2D color map, and not a height map. The value of the stress should specifiy the hight of the points over the surface made of x and z.

Once again thank you for your time, I will accept the answer as soon as this is solved.

[KSSV]

That would be possible with Option 2...remove the view(2) command in there..try rotating the plot...I hope this is what you are expecting.

[Malthe Gissel]

Thank you very much! This is exactly what I was trying to do!