Repeated elements in an array

if I have:

A=[3 7 25 27 30 31 32 34 35 36]

B=[2 4 2 2 2 0 3 2 3 2]

How can I have the index of the first element repeated in B and use it in A to have :

A=[3 7 25 31 32 34 35 36]

B=[2 4 2 0 3 2 3 2]

I used diff(B), but it will give:

A=[3 7 30 31 32 34 35 36]

B=[2 4 2 0 3 2 3 2]

(30 instead of 25, 30 represents the last element in B that has value of 2; or what I want is the first element in B that has value of 2 which is 25 in my case).

Is there any logic way or i should use a loop?

Answer 1

[Stephen23]

A = [3 7 25 27 30 31 32 34 35 36];
B = [2 4 2 2 2 0 3 2 3 2];

Either define new variables:

X = [true,diff(B)~=0];
C = A(X)

C = 1×8

3 7 25 31 32 34 35 36

D = B(X)

D = 1×8

2 4 2 0 3 2 3 2

or if you really want to remove elements from A and B:

Y = [false,~diff(B)];
A(Y) = []

A = 1×8

3 7 25 31 32 34 35 36

B(Y) = []

B = 1×8

2 4 2 0 3 2 3 2

[Rim Abdallah]

Thank you, it works!