Finding position of value in an array

I'm working on some code and here's a portion of it

clear all; close all; clc;
y = [-3.2628   -2.4774   -1.6920   -0.9066   -0.1212    0.6642    1.4496    2.2350    3.0204];
x=-2.8701; 
for i=1:length(y)-1
    if (x>=y(i) && x <=y(i+1))
        x=i-1;
    end
    
end

The answer i'm getting is

x =

     4
     

I expect x=0. Is there anything I'm doing wrong?

Answer 1

[Cris LaPierre]

The first thing that jumps out to me is that you replace your x value with your counter value. As the loop progresses, your if statement is no longer comparing to x=-2.8701.

Perhaps you want it to stop after if finds the first true case? If so, add break after x=i-1 to stop the for loop.

Answer 2

[Julius Muschaweck]

clear all; close all; clc;
y = [-3.2628   -2.4774   -1.6920   -0.9066   -0.1212    0.6642    1.4496    2.2350    3.0204];
x=-2.8701; 
for i=1:length(y)-1
    if (x>=y(i) && x <=y(i+1))
        XXXX =i-1; % do not use x -- you will overwrite -2.8701 with 0, which 
        % will then match for i = 5
    end
    
end