Ho do I make a matrix with point data?

I currently have data for 3d points and want to make a matrix out of them

This point data is structured as 3 matrices each containing x, y, z locations which look like these

x=[-3.266573190689087, -3.266134023666382, -3.266134023666382, -3.266573190689087, ... ]

y=[-0.372330516576767, -0.372330516576767, -0.371891230344772, -0.371451914310455, ... ]

z=[-0.085013940930367, -0.085015110671520, -0.084998413920403, -0.085046470165253, ... ]

My hope is to find a way to combine these three matrices into one matrix which would be

matrix( y(i) , x(i) ) = z(i)

x,y,z are all 168136818 long so I dont thick I can share them due to their size

Is there a way to do this in matlab?

thank you for your help.

Answer 1

[KSSV]

Let A be your m*3 data matrix.

x = A(:,1) ; y = A(:,2) ; z = A(:,3) ;

%%structured 
xi = unique(x) ; yi = unique(y) ;
[X,Y] = meshgrid(xi,yi) ;
Z = reshape(z,size(X)) ;
figure
surf(X,Y,Z)
%%unstructured 
dt = delaunayTriangulation(x,y) ;
tri = dt.ConnectivityList ;
figure
trisurf(tri,x,y,z)

[Hoyong Yie]

Thank you very much,

But I am getting an error during reshape part

[Error using reshape

Number of elements must not change. Use [] as one of the size inputs to automatically calculate the appropriate

size for that dimension.]

I looked through the reshape function but can't find what might cause this problem.

Can you help me?

[KSSV]

Your data is scattered or structured?

[Hoyong Yie]

If structured means the matrix is full, I think it's mostly structured, where the end parts have some holes

[KSSV]

Attach your data.

[Hoyong Yie]

This would be the A part of my data

[KSSV]

There is no data in .mat file. It shows 0kb.

[Hoyong Yie]

I think it was because the size was over 400MB

https://drive.google.com/drive/folders/14do3pC7LnKeDRyM1R3396GybqE77z6mn?usp=sharing

would sharing like this be ok?

[KSSV]

You have to give permission to access...

[Hoyong Yie]

Done. Sorry for the inconvenience. I never shared a file like this before.

[KSSV]

x = A(:,1) ;
y = A(:,2) ; 
z = A(:,3) ; 
% Use grid data to get matrices
dx = 0.05 ; dy = 0.05 ;   % specify your resolution 
xi = min(x):dx:max(x) ; 
yi = min(y):dy:max(y) ; 
[X,Y] = meshgrid(xi,yi) ;
Z = griddata(x,y,z,X,Y) ;

pcolor(X,Y,Z)
shading interp 
colorbar

[Hoyong Yie]

thank you very much,

but can you tell me what does idx means?

[KSSV]

You can remove the idx. I forgot to remove it while answering. I worked with reduced data as data was huge, so I have used idx and indices to pick some part of data.

[Hoyong Yie]

Ok thank you.

I'm quite new to matlab and was stuck with this for 2 weeks.

Your help is greatly appreciated.

[KSSV]

You are welcome...my pleasure helping you. :)