Delete some specific numbers from an array
1 view (last 30 days)
Show older comments
So, the problem is like this. I have an array of random numbers. For example [10 9 5 5 7 3 5 8 3 5 6 3 7 10 ]. First, I have to delete some of the numbers to make any point's value can not between its adjecent numbers. For example 9 is between 10 and 5, so I will delete 9. I tried to use a for loop but that does not work.
2 Comments
Walter Roberson
on 2 Oct 2019
Hint: sign(diff(TheVector)) will be the same for two entries in a row if the middle value is between the two other values (or if the three values are all equal)
Answers (2)
Andrei Bobrov
on 2 Oct 2019
Edited: Andrei Bobrov
on 3 Oct 2019
A = [10 9 5 5 7 3 5 8 3 5 6 3 7 10 ];
B = sign(diff(A(hankel(1:3,3:numel(A)))',1,2));
out = A( [true; prod(B,2) ~= 1 ; true] );
Rongyu Chu
on 3 Oct 2019
3 Comments
Walter Roberson
on 3 Oct 2019
Index from highest to lowest so that when you delete, you do not need to examine the entries that "fell down".
See Also
Categories
Find more on Matrices and Arrays 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!