Sum only consecutive positive numbers and place the sum in a new vector in specific positions
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Hi!
I have this variable P1 (attached) and i want to make the sum of ONLY consecutive positive values and place the sum in a new vector (out) in the position that you can see in Figure. In there is only one value you can place it in the same position of P1, otherwise, place it in the lowest consecutive positive position. For the other values of out i want zero.
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/278648/image.png)
I tried with this but it is not doing what i want...
Thanks in advance!!!
lo = P1 > 0;
h5 = cumsum(diff([0;lo(:)]) == 1).*lo(:);
out = accumarray(h5 + 1,P1);
回答(1 个)
Thiago Henrique Gomes Lobato
2020-3-22
Try this:
lo = P1 > 0;
Dfference = diff([lo(:);0]);
Ends = find(Dfference==-1); % -1 are the positions where a sequence ends
Start = find(Dfference==1)+1; % 1 are the positions where a sequence starts -1
% loop only over the founded sequences
out = zeros(size(P1));
for idx=1:length(Start)
out(Ends(idx)) = sum(P1(Start(idx):Ends((idx))));
end
7 个评论
Thiago Henrique Gomes Lobato
2020-4-5
Add those changes:
if length(Ends)>length(Start)
Start = [Ends(1);Start];
end
SP = zeros(size(P1));
for idx=1:length(Start)
End = min(Ends(idx)+2,length(P1));
SP(Ends(idx):End) = sum(P1(Start(idx):Ends((idx)))); % this is the part of code you missed in the previous answer
end
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