To plot the surface only within the specified bounds, you need to mask the values outside the bounds. This can be achieved by setting the Z values to NaN where the points fall outside the desired region. Here's how you can do it:
- Define the bounds as logical conditions.
- Apply these bounds to mask out the unwanted parts of the surface.
xmin1 = 0;
xmax1 = 1;
xmax2 = 2;
ymin1 = @(x) 0.25 * x.^2;
ymax1 = @(x) x.^(1/3);
x1 = 0:0.05:1;
x2 = 1.05:0.05:2;
xAll = 2:-0.05:0;
yTop1 = ymax1(x1);
yTop2 = ones(1, length(x2));
yBot = ymin1(xAll);
% Define the function
fun = @(x, y) sin(4 .* x) + y.^2 + 2;
% Create meshgrid
[X, Y] = meshgrid(0:0.05:2, 0:0.05:1);
Z = fun(X, Y);
% Mask Z values outside the bounds
mask = false(size(X));
% Apply the bounds to create the mask
for i = 1:length(X(:))
x = X(i);
y = Y(i);
if (x >= xmin1 && x <= xmax1 && y >= ymin1(x) && y <= ymax1(x)) || ...
(x > xmax1 && x <= xmax2 && y >= ymin1(x) && y <= 1)
mask(i) = true;
end
end
Z(~mask) = NaN;
% Plot the surface
figure
surf(X, Y, Z);
hold on
% Plot the 2D fill for reference
fill([x1 x2 xAll], [yTop1 yTop2 yBot], 'b');
hold off
- The "mask" array is created to identify the points within the specified bounds.
- The Z values outside the bounds are set to "NaN" to mask them.
