## How to plot A Curve That Connects The Highest Values in Y-Axis

### Yaser Khojah (view profile)

on 26 Apr 2019
Latest activity Edited by Yaser Khojah

on 29 Apr 2019

### Naman Bhaia (view profile)

Can anyone please help me to create the curve as below. I'm looking for away to plot the highest point at y-axix for all x-axis. I attached my data and plot as below.
scatter(MaT_All(:,18), MaT_All(:,17))

darova

on 26 Apr 2019
Yaser Khojah

### Yaser Khojah (view profile)

on 26 Apr 2019
Dear darova,
I want to focus on the top part only and I need to extract these data to do more analyse.

### Naman Bhaia (view profile)

on 29 Apr 2019

Hello Yaser,
I believe the issue you are facing can be solved in two steps:
1. Find the maximum value corresponding to each value of x. For this, you can visit this MATLAB Answer thread and see if it helps.
2. Plot the values found in the previous step to form the upper boundary .

Yaser Khojah

### Yaser Khojah (view profile)

on 29 Apr 2019
Dear Naman, I have looked into it but I have one question as my code below. How to find the index of the ymax?
x = round(MaT_All(:,18),0);
y = MaT_All(:,17);
[uv,~,idx] = unique(x);
ymax = accumarray(idx,y,[],@max); %build matrix
figure
scatter(uv,ymax)
line(uv,ymax)
I alost tired the following and I still need to find the index of (Resutl)
Result = splitapply(@max, y, idx);
figure
scatter(uv,Result)
line(uv,Result)