how to solve the error "Unable to perform assignment because the indices on the left side are not compatible with the size of the right side"

I am unable to solve the error I am facing. It's with the ax,ay, az and I think the problem is either in the way I am implementing them or in the stuff in their equations, the xs,ys,zs or the X,Y,Z. Please if someone can have a look at the code below I commented which line the error is. Maybe someone can advise me how to fix it. Thanks.

clear all; 
clc;
load data3.csv
c=299792458;
newdata=[];
shj=1;
i=1;
N=1;
SecOfDay=30;
counter_1=0; %counts how many rows belongs to the same seocnds in the data

for S=1:length(data3)
    if(data3(S,6)>15)
        newdata(i,:)=data3(S,:);
        i=i+1;
    end
end
                
while N<length(newdata)
    for r=1:length(newdata)
        if(SecOfDay==newdata(r,1))
            counter_1=counter_1+1;
        end              
                xs=newdata(N:counter_1,3);
                ys=newdata(N:counter_1,4);
                zs=newdata(N:counter_1,5);
                dist=newdata(N:counter_1,6); 
    end     
                Fun = @(u) [sqrt((xs-u(1)).^2 + (ys-u(2)).^2 + (zs-u(3)).^2) - (c*u(4)) - (dist)];
                x0 = [0;0;0;0];
                u = lsqnonlin(Fun,x0);
                SecOfDay=SecOfDay+30; 
                
                X=u(1);
                Y=u(2);
                Z=u(3);
                ERROR=u(4);
                
               
                r= sqrt((xs-X).^2-(ys-Y).^2-(zs-Z).^2);
                ax(N:counter_1)=(xs-X)/r;     %the error is at this line 
                ay(N:counter_1)=(ys-Y)/r;
                az(N:counter_1)=(zs-Z)/r; 
                
                N=counter_1+1;
                
                H=[ax ay az 1];
                
                            
                for i=N:counter_1
                  HH=[H; ax(i) ay(i) az(i) 1];            
                end            
end 

[Image Analyst]

You forgot to read the posting guidelines:

TUTORIAL: How to ask a question (on Answers) and get a fast answer

I can format your code for you (which I did by selecting it and clicking the code icon), but I can't attach "data3.csv" for you because I don't have it. Most people won't look at this until they can run your (mostly uncommented) code, which means having your CSV file.

And did you see the answer in your duplicate question:

https://www.mathworks.com/matlabcentral/answers/882668-how-to-implement-this-in-a-better-way-or-what-is-the-mistake#comment_1649603

[MA]

thank you for your comment, and my apologizes I forgot to attach the CSV file but its now attached above.

[Image Analyst]

Sorry I can't help:

'lsqnonlin' requires Optimization Toolbox.

Error in test3 (line 40)

u = lsqnonlin(Fun,x0);

However, I did add that to the Product list so that others without the toolbox won't waste their time.

[MA]

No issuies. thank you again, really appreciate it.

Answer 1

[KSSV]

The error is clear, this error pops out when you are trying to save more number of elements than the initialized array.

Example:

A = zeros(5,5) ;        % A is 5*5 matrix initialized 
A(1,:) = rand(1,5) ;  % no error as 5 elements are saved 
A(2,:) = rand(1,7) ; % error becuase in second row of A should have 5 elemnts 

Check the matrix you have intiliazed. If you are not aware of of the dimensions, store them in a cell array.

A = cell(5,1) ; 
A{1} = rand(1,5) ; 
A{2} = rand(1,6) ;