How to mark the maximum of a surf plot

Hello,

I want to mark the maximum of a surf plot, thats my code, but it isn't working and always puts out a false maximum:

alpha=50;

beta=20;

t=trnd(1,1,20);

x=alpha+beta*t;

a = linspace(35,65,1000);

b = linspace(-50,50,1000);

[a2,b2,x2] = meshgrid(a,b,x);

likeli=prod(b2./(pi*((x2-a2).^2+b2.^2)),3);

[maxV, maxL] = max(likeli(:));

[maxa, maxb] = ind2sub(size(likeli),maxL)

figure

contour(likeli,50)

hold on

axis auto

xline(maxa,'r')

yline(maxb,'r')

hold off

Answer 1

[Karim]

I'm guessing you switched maxa and maxb. Note that the columns are plotted on the x axis and the rows on the y axis.

alpha=50;
beta=20;
t=trnd(1,1,20);
x=alpha+beta*t;
a = linspace(35,65,1000);
b = linspace(-50,50,1000);
[a2,b2,x2] = meshgrid(a,b,x);
likeli=prod(b2./(pi*((x2-a2).^2+b2.^2)),3);


[maxV, maxL] = max(likeli(:));
[maxa, maxb] = ind2sub(size(likeli),maxL)

maxa = 371

maxb = 359

figure
contour(likeli,50)
hold on
axis auto
xline(maxb,'r')
yline(maxa,'r')
hold off

% have a look in 3D
figure
surf(likeli,'EdgeColor','none')
hold on
axis auto
scatter3(maxb,maxa,maxV,50,'r','filled')
hold off
view(3)

[Maria Anna]

Ohhh yes of course, thank you