# Creating Surface Plot from a Matrix with 3 Columns

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Sarah on 30 Jul 2018
Answered: KSSV on 9 Oct 2021
How do you create a surface plot using a matrix with 3 columns in Matlab? The first column would be the x-values, the second column would be the y-values, and the third column would be the z-values for the surface plot.
KSSV on 30 Jul 2018
More data is needed.

KSSV on 30 Jul 2018
A = [0.5000 0.5000 66.9052
0.5000 1.0000 57.3591
1.0000 0.5000 76.7805
1.0000 1.0000 66.9052] ;
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)
Hans Kramer on 30 Mar 2021

KSSV on 9 Oct 2021
x = speed ; y = Torque ; z = bsfc ;
%%structured
xi = unique(x) ; yi = unique(y) ;
[X,Y] = meshgrid(xi,yi) ;
Z = reshape(z,size(X)) ;
figure
pcolor(X,Y,Z)
%% griddata
xi = linspace(min(x),max(x));
yi = linspace(min(y),max(y)) ;
[X,Y] = meshgrid(xi,yi) ;
Z = griddata(x,y,z,X,Y)
pcolor(X,Y,Z)