Find Unique values in array

Hi all,

I am trying to create a new array contains ONLY the unique values (same values but not repeated) which in the following case are 90 0 45

I used unique function, however, the function also returns the same data as in x, but in sorted order. I DO NOT want them in sorted order,

Also, I would like to obtain the index of the unique values in the x

like index=[1,2,9]

clear all;
clc;
x=[90 0 0 90 90 90 90 90 45 0 0 0]; 
y=unique(x)

Answer 1

[Ameer Hamza]

clc;
x=[90 0 0 90 90 90 90 90 45 0 0 0]; 
[y, idx] = unique(x, 'stable')

output

y =
    90     0    45
idx =
     1
     2
     9

[Ali Tawfik]

@ Ameer Thanks, working perfectly,

just one more question, now the output sometimes, for the multidimensional array will be :

y(:,:,1)

y(:,:,2)

y(:,:,3)

y(:,:,4)

However, the two middle array are equal to zero , is it a way to only the output with values !!

clear all;
clc; 

A(:,:,1) = [10;20]; 
A(:,:,2)=[1;2]
A(:,:,3)=[1;2]
A(:,:,4)=[100;200]
A(:,:,5)=[1;2]

for i=[1,4]
    z(:,:,i)=A(:,:,i)
end 

[Ameer Hamza]

Correct syntax is i=1:4 (use colon)

for i=1:4
    z(:,:,i)=A(:,:,i)
end 

[Ali Tawfik]

Hi,

Thanks for your prompt reply.

I understand, but I am looking for ONLY for index 1 and 4

So I wanna my output to be

z(:,:,1) = [10;20];

z(:,:,4)=[100;200]; which should be z(:,:,2)

[Ameer Hamza]

Try try something like this

idx = [1 4];
for i=1:numel(idx)
    z(:,:,i)=A(:,:,idx(i))
end