# 2 variable for-loop

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mehra on 4 Nov 2019
Commented: mehra on 4 Nov 2019
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?

Bob Nbob on 4 Nov 2019
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.

#### 1 Comment

mehra on 4 Nov 2019
Thanks Bob