For loop index assistance

I have these nested for loops. I'm trying to output these delta_K_estimate values but it keeps populating with the same values from 1:101, 102:202, 203:303, etc. Each value across all columns should vary and be different from the previous. I'm sure it's some small index error that i'm missing but can't see. Thanks in advance for you help!

P=zeros(length(transpose(K_hat)),2); 
delta_K_estimate=zeros(82,505);
for i=0:number_of_peaks-1 %each peak
    for j=(101*i)+1:(101*i)+101 %each C_avg  
         P(j,:)=polyfit(K_hat(:,j),delta_K(:,i+1),1); %determination of linear fit equation
        delta_K_estimate(:,j)=P(j,1).*K_hat(:,j)+P(j,2); %linear fit estimate of delta_K
     end
 end

[Image Analyst]

Can you attach K_hat and delta_K in a .mat file?

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

[Dominic Piedmont]

I don't think that's really necessary for answering a syntax/indexing error. I'm sure random data will suffice.

[dpb]

Well, knowing the sizes would certainly help even w/o specific data to be able to try to read the code without making up stuff.

NB:

P=zeros(length(transpose(K_hat)),2); 

length(X) is defined as max(size(X)) so you may, or may not, have the result there that is expected. Use the proper size() dimension argument needed to ensure robust code.

delta_K_estimate(:,j)=polyval(P(j,:),K_hat(:,j)); %linear fit estimate of delta_K

Answer 1

[Star Strider]

I do not understand the reason you are indexing ‘j’ as a for loop.

I would do something like this to get consecutive ‘j’ vectors of length 100, beginning at 1, 101, 201, 301, ...

for i=1:number_of_peaks %each peak
    j = (1:100)+100*(i-1);
    P(j,:)=polyfit(K_hat(:,j),delta_K(:,i+1),1); %determination of linear fit equation
    delta_K_estimate(:,j)=P(j,1).*K_hat(:,j)+P(j,2); %linear fit estimate of delta_K
 end