Removing repeated in order elements from array?

3 次查看（过去 30 天）
Nicholas Kavouris
Nicholas Kavouris 2022-3-30
评论： Voss 2022-3-30
I have an array like [ 1 1 1 2 2 3 3 3 1 1 1 2 2 4 4 4 5 5 6]
Is there a method which will produce array [ 1 2 3 1 2 4 5 6] and remove all repeating orderly values but not remove all duplicates?
have tried code below with no luck
for k=length(array):-1:1
if array(k)==array(k+1)
array(k)=[]
end
end

请先登录，再回答此问题。

回答（2 个）

Rik
Rik 2022-3-30
Ran in:
No need for a loop (even if you should have replaced length by numel):
data=[ 1 1 1 2 2 3 3 3 1 1 1 2 2 4 4 4 5 5 6];
L=diff(data)==0; % note: this is 1 element shorter that data itself
data(L)=[]
data = 1×8
1 2 3 1 2 4 5 6
Voss
Voss 2022-3-30
Ran in:
Your approach will work; you just have to start at the second-to-last element instead of the last:
array = [ 1 1 1 2 2 3 3 3 1 1 1 2 2 4 4 4 5 5 6];
for k=length(array)-1:-1:1
if array(k)==array(k+1)
array(k)=[];
end
end
array
array = 1×8
1 2 3 1 2 4 5 6
Here's another approach:
array = [ 1 1 1 2 2 3 3 3 1 1 1 2 2 4 4 4 5 5 6];
array(diff(array) == 0) = [];
array
array = 1×8
1 2 3 1 2 4 5 6
  3 个评论
显示 1更早的评论
Torsten
Torsten 2022-3-30
编辑：Torsten 2022-3-30
Why not ? I get
array = [2]
It's because diff(array) has one element less than array.
Voss
Voss 2022-3-30
Ran in:
As @Torsten says, it should still work (both ways work):
array = [2 2 2 2 2 2 2];
for k=length(array)-1:-1:1
if array(k)==array(k+1)
array(k)=[];
end
end
array
array = 2
array = [2 2 2 2 2 2 2];
array(diff(array) == 0) = [];
array
array = 2

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Matrix Indexing 的更多信息

标签

产品


版本

R2021b

Community Treasure Hunt

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

Start Hunting!

Translated by