How can I find the index of a specific element in an array
3 次查看(过去 30 天)
显示 更早的评论
I have a vector T of size 1 by 30. The values of its elements start from zero and go to a maximum value and then decay back to zero.
How can I find the index of the element that satisfies <= .05 * R only in the decaying region of T?
R = 5000;
T = [0 8 39.3 103 236.5 511.7 1026.1 1906.9 3148.7 4293 4011.9 2628.4 1037.4 203.7 28.6 9.4 4.2 1.4 1.3 0.6 0.1 0 0 0 0 0 0 0 0 0]
Thanks
0 个评论
采纳的回答
Walter Roberson
2021-11-27
R = 5000;
T = [0 8 39.3 103 236.5 511.7 1026.1 1906.9 3148.7 4293 4011.9 2628.4 1037.4 203.7 28.6 9.4 4.2 1.4 1.3 0.6 0.1 0 0 0 0 0 0 0 0 0];
[~, maxidx] = max(T);
idx = find( (T <= 0.05 * R) & (maxidx <= 1:length(T)) )
更多回答(1 个)
KSSV
2021-11-27
R = 5000;
T = [0 8 39.3 103 236.5 511.7 1026.1 1906.9 3148.7 4293 4011.9 2628.4 1037.4 203.7 28.6 9.4 4.2 1.4 1.3 0.6 0.1 0 0 0 0 0 0 0 0 0] ;
x = 1:length(T);
%Get max value from T
[val,id] = max(T) ;
% Condition
idx = find(T<=0.5*R) ;
% Pick only those greater then id
idx(idx<id)=[];
plot(x,T)
hold on
plot(x(idx),T(idx),'*r')
另请参阅
类别
在 Help Center 和 File Exchange 中查找有关 Matrix Indexing 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!