How to detect a peak from a 2D graph

I want to find the x, and y values that makes up the peak. I have attach the image for better clarification. I tried to use the codes below to obtain the values. There are three peaks but i get extra peaks from my code. Besides, i have trouble finding the rigth X, and Y values that makes up the peaks. Your assistance is highly appreciated.

tt1=0:1:90; 
tt2=0:1:90;
figure(1)  
PPM=10*log10(PPM); 
figure(1)  %??? 
mesh(tt1,tt2,PPM) 
%axis([0,90,0,90]) 
xlabel('x') 
ylabel('y') 

[pks,locs] = findpeaks(PPM); 
  	angs = tt1(locs)'; 
	angs = tt2(locs)'; 

[Rik]

I don't have the required toolbox, so I can't test this myself, but have you tried the other inputs and output of findpeaks? Specifically the prominence? That sounds like something you could try. If you are certain there will always be exactly 3 relevant peaks, you could even use it to select the 3 peaks with the highest prominence.

Answer 1

[Zhangxian Deng]

MATLAB introduced a new function called "islocalmax2" in R2024a.