How to find corresponding value in two arrays?

Hi,

I have to data arrays, A and B. I want to knwo how it is possible to find corresponding number or value of the element in B array when accumulation in A array reaches certain value? Basically, I want to elements in array A until the sum reaches prescribed value. Then I need to know what was the corresponding value in B array when the condition is met. How can I do this? Cannot find a way my own...

Thanks

Answer 1

[Chad Greene]

A = rand(1,100); 
B = rand(1,100); 
MyBElements = B(cumsum(A)<10)

Above, MyBElements is all the elements in B until the cumulative sum of A reaches 10.

Plotting the cumulative sum of A, a threshold at 10, and the individual elements of A, B, and MyBElements can be done like this:

figure; 
subplot(2,1,1)
plot(cumsum(A)); 
hold on
plot([1 100],[10 10],'r')
axis tight 
title('cumulative sum of A') 

subplot(2,1,2)
plot(1:100,A,'b+',1:100,B,'rx')
hold on 
box off
plot(MyBElements,'ro')
legend('A','B','MyB')

[Andrejus]

Thanks, that worked great. I have spent 2 days for this and you solved easily. Super thanks!