Failing in creating a surface from three array

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SYML2nd
SYML2nd 2022-9-2
编辑： Torsten 2022-9-2
I am trying to create a surface from this dataset
x=[0.5 ; 0.624; 0.75;0.874; 0.9;1;1.124]
y=[0; 1.1;1; 0.9;0.6;0]
z=[0.726582; 0.629144; 0.714131; 0.499709; 0.668832; 0.664573]
I am using this code found in here
xi = unique(x) ; yi = unique(y) ;
[X,Y] = meshgrid(xi,yi) ;
Z = reshape(z,size(X)) ;
figure
surf(X,Y,Z)
but I get this error
"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.
Error in untitled2 (line 8)
Z = reshape(z,size(X)) ;"
I cannot understand what I am doing wrong.

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采纳的回答

Star Strider
Star Strider 2022-9-2
编辑：Star Strider 2022-9-2
Ran in:
Use one of the interpolation functions (here griddata) to create the ‘Z’ matrix —
x=[0.5 ; 0.624; 0.75;0.874; 0.9;1.124];
y=[0; 1.1;1; 0.9;0.6;0];
z=[0.726582; 0.629144; 0.714131; 0.499709; 0.668832; 0.664573];
N = 10;
xv = linspace(min(x), max(x), N);
yv = linspace(min(y), max(y), N);
[X,Y] = ndgrid(xv, yv);
Z = griddata(x, y, z, X, Y);
figure
surfc(X, Y, Z)
grid on
xlabel('X')
ylabel('Y')
zlabel('Z')
view(70,30)
.

更多回答（1 个）

Torsten
Torsten 2022-9-2
To create a surface, you need a z value for each combination of (x/y) values. Thus instead of a vector z with 6 elements you need a matrix of size (7x6).
  2 个评论
SYML2nd
SYML2nd 2022-9-2
Can you show me how to obtain a matrix (7x6)? Do you mean (6x7) by doing Z=[Z,Z,Z,Z,Z,Z,Z] (I tried but it doesnt work)
Torsten
Torsten 2022-9-2
编辑：Torsten 2022-9-2
Ran in:
x=[0.5 ; 0.624; 0.75;0.874; 0.9;1;1.124];
y=[0; 1.1;1; 0.9;0.6;0];
z=[0.726582; 0.629144; 0.714131; 0.499709; 0.668832; 0.664573];
[X,Y] = meshgrid(x,y);
Z = repmat(z,1,7);
surf(X,Y,Z)
But the surface plot only makes sense if you really have a function f with z(i,j) = f(x(i),y(j))

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