2 variable for-loop

hello

I have the following code which I want to write it as a two variable for loop, Apparently I am making mistake that it gives the same values for all elements of results matrix

TKE_dave is a 19000*13 matrix

and

tp =[4833 6499 8165 9831 11497 13163 14829 16495 18161]

TKE_ave1=TKE_dave(:,1);
 TKE_avep1=zeros(8,1);
 for m=1:8
     TKE_avep1(m,1)=nanmean(TKE_ave1(tp(m):tp(m+1)));
 end
 
 TKE_ave2=TKE_dave(:,2);
 TKE_avep2=zeros(8,1);
 for m=1:8
     TKE_avep2(m,1)=nanmean(TKE_ave2(tp(m):tp(m+1)));
 end 
 
  TKE_ave3=TKE_dave(:,3);
 TKE_avep3=zeros(8,1);
 for m=1:8
     TKE_avep3(m,1)=nanmean(TKE_ave3(tp(m):tp(m+1)));
 end
 
   TKE_ave4=TKE_dave(:,4);
 TKE_avep4=zeros(8,1);
 for m=1:8
     TKE_avep4(m,1)=nanmean(TKE_ave4(tp(m):tp(m+1)));
 end
 
   TKE_ave5=TKE_dave(:,5);
 TKE_avep5=zeros(8,1);
 for m=1:8
     TKE_avep5(m,1)=nanmean(TKE_ave5(tp(m):tp(m+1)));
 end
  
   TKE_ave6=TKE_dave(:,6);
 TKE_avep6=zeros(8,1);
 for m=1:8
     TKE_avep6(m,1)=nanmean(TKE_ave6(tp(m):tp(m+1)));
 end
   
   TKE_ave7=TKE_dave(:,7);
 TKE_avep7=zeros(8,1);
 for m=1:8
     TKE_avep7(m,1)=nanmean(TKE_ave7(tp(m):tp(m+1)));
 end
 
    TKE_ave8=TKE_dave(:,8);
 TKE_avep8=zeros(8,1);
 for m=1:8
     TKE_avep8(m,1)=nanmean(TKE_ave8(tp(m):tp(m+1)));
 end
 
    TKE_ave9=TKE_dave(:,9);
 TKE_avep9=zeros(8,1);
 for m=1:8
     TKE_avep9(m,1)=nanmean(TKE_ave9(tp(m):tp(m+1)));
 end
 
     TKE_ave10=TKE_dave(:,10);
 TKE_avep10=zeros(8,1);
 for m=1:8
     TKE_avep10(m,1)=nanmean(TKE_ave10(tp(m):tp(m+1)));
 end

     TKE_ave11=TKE_dave(:,11);
 TKE_avep11=zeros(8,1);
 for m=1:8
     TKE_avep11(m,1)=nanmean(TKE_ave11(tp(m):tp(m+1)));
 end
 
      TKE_ave12=TKE_dave(:,12);
 TKE_avep12=zeros(8,1);
 for m=1:8
     TKE_avep12(m,1)=nanmean(TKE_ave12(tp(m):tp(m+1)));
 end
 
      TKE_ave13=TKE_dave(:,13);
 TKE_avep13=zeros(8,1);
 for m=1:8
     TKE_avep13(m,1)=nanmean(TKE_ave13(tp(m):tp(m+1)));
 end 

I tried to make it shorter and write it as the following two variable for-loop and for that I learend that I have to define a temporary matrix so I defined test matrix which is the same as TKE_dave actually

     TKE_avep=zeros(8,13);
     test=zeros(19000,13);
     for m=1:8;
         for ss=1:13;
        test(:,ss)=TKE_dave(:,ss);
        TKE_avep(m,ss)=nanmean(test(tp(m):tp(m+1)));
         end
     end

but it gives the same values for all the elemants of the result matrix.

can someone help me where is my mistake?

Answer 1

[Bob Thompson]

The issue is with your definition of test. Nested for loops are totally fine.

test(:,ss)=TKE_dave(:,ss); 

On your last loop test and TKE_dave will be the same matrix, whereas in your individual loops it is only each column. Replace test(:,ss) with just test.

[mehra]

Thanks Bob