Separate correctly values in array

4 views (last 30 days)
Ana Gabriela Guedes
Ana Gabriela Guedes on 17 Apr 2021
Edited: Jan on 17 Apr 2021
Hi!
I have 2 vectors: A = [7.046, 15.66, 24.16, 31.476, 39.42, 62.86, 69.83, 91.326, 98.586,106.672, 114.722] corresponds to the instants when some event A occured and
B = 0.53, 1.25, 2.01, 2.78, 3.51, 4.25, 4.96, 5.78, 6.55, 7.26, 7.98, 8.76, 9.54, 10.32,11.08, 11.77, 12.43, 13.68, 14.77, 15.57, 16.31. 17.08, 17.92, 18.72, 19.5, 20.23, 20.9, 21.74, 22.55, 23.36, 24.17, 24.9, 25.68] that corresponds to the instants in which event B is happening.
I want to separate the difference between each B value occuring before and after each event_A and save that values in separate vectors maybe.
For example I would have [B(2)-B(1) B(3)-B(2) ... B(9) - B(8)] (since B(9) = 6.55 < A(1)= 7,046). Then, I would save this vector in a cell array(dont know if there's a better way) and start calculating the differences after A(1) and before A(2): [B(10)-B(9) ... B(20) - B(19)] (since B(20) = 15.57 < A(2) = 15.66) and do this until A(end).
I tried to do this but the cell array always keeps the differences between all B values since B(1) until the last B<A(i) instead of only the intervals I want.
How can I correct the following code to do what I want?
A = [7.046, 15.66, 24.16, 31.476, 39.42, 62.86, 69.83, 91.326, 98.586,106.672, 114.722];
B = 0.53, 1.25, 2.01, 2.78, 3.51, 4.25, 4.96, 5.78, 6.55, 7.26, 7.98, 8.76, 9.54, 10.32,11.08, 11.77, 12.43, 13.68, 14.77, 15.57, 16.31. 17.08, 17.92, 18.72, 19.5, 20.23, 20.9, 21.74, 22.55, 23.36, 24.17, 24.9, 25.68];
result = {};
dif_vector = [];
for i = 1:length(A)
for j = 1:(length(B))-1
if i == 1
if B(j+1) < A(1)
dif = B(j+1)-B(j);
dif_vector= [dif_vector dif];
end
else
if (B(j) > A(i-1) && B(j+1) < A(i))
dif = B(j+1)-B(j);
dif_vector= [dif_vector dif];
end
end
end
result = [result dif_vector];
end

Accepted Answer

Jan
Jan on 17 Apr 2021
Edited: Jan on 17 Apr 2021
A = [7.046, 15.66, 24.16, 31.476, 39.42, 62.86, 69.83, 91.326, 98.586,106.672, 114.722];
B = [0.53, 1.25, 2.01, 2.78, 3.51, 4.25, 4.96, 5.78, 6.55, 7.26, 7.98, 8.76, ...
9.54, 10.32,11.08, 11.77, 12.43, 13.68, 14.77, 15.57, 16.31, 17.08, ...
17.92, 18.72, 19.5, 20.23, 20.9, 21.74, 22.55, 23.36, 24.17, 24.9, 25.68];
nResult = find(A > B(end), 1); % or: numel(A)
result = cell(1, nResult);
iB1 = 1;
for iA = 1:nResult
iB2 = find(B < A(iA), 1, 'last');
result{iA} = diff(B(iB1:iB2));
iB1 = iB2 + 1;
end
Alternatively:
[~, idx] = sort([B, A]);
wasA = (idx > numel(B));
v = cumsum(wasA) + 1;
result = splitapply(@(x) {diff(x)}, B, v(~wasA))

More Answers (0)

Categories

Find more on Matrix Computations in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!