# 2 vectors compare it

2 views (last 30 days)
Joshua Folorunso on 9 Nov 2022
Commented: Rena Berman on 27 Dec 2022
Hello, Ineed help with this question. I have 2 vectors to compare. Matrix below is a simplified vector with 2 columns that I want to compare. I want to move across the columns from column 1 to column 2 to column 1 continously till the end of the vector in an ascending order. If I move across , I record a value +ve, if I move within the same column, I record -ve. E.g
2 to 3 is +ve
3 to 4 is +ve
4 to 5 is +ve
5 to 7 is -ve( same column)
7 to 9 is -ve of -ve = +ve (same column movement)
9 to 10 is +ve
10 t0 12 is +ve
12 to 16 is +ve
16 to 17 is -ve
17 to18 is +ve
18 to 19 is +ve
19 to20 is +ve
Rena Berman on 27 Dec 2022

Matt J on 9 Nov 2022
Edited: Matt J on 9 Nov 2022
I will assume here that the oddity mentioned above by @Dyuman Joshi is an error in the presentation of the example.
A=[2 3
4 5
10 7
15 9
16 12
17 18
19 20];
A=A';
B=A*0+[1;2];
[~,is]=sort(A(:));
B=2*abs(diff(B(is))')-1 %result
B = 1×13
1 1 1 -1 -1 1 1 1 -1 -1 1 1 1
Joshua Folorunso on 9 Nov 2022
Yes.
This is correct now. Thank you very much.

Bruno Luong on 9 Nov 2022
Edited: Bruno Luong on 9 Nov 2022
A=[2 3
4 5
10 7
15 9
16 12
17 18
19 20];
[As,is] = sort(A(:));
col = 1 + (is>size(A,1));
Vesign = 2*~~diff(col)-1;
Vesign = cumprod(Vesign);
Ves = string(Vesign);
Ves = repmat("+", size(Vesign));
Ves(Vesign<0) = "-";
S = As(1:end-1);
T = As(2:end);
col_S = col(1:end-1);
col_T = col(2:end);
T = table(S,T,col_S,col_T,Ves)
T = 13×5 table
S T col_S col_T Ves __ __ _____ _____ ___ 2 3 1 2 "+" 3 4 2 1 "+" 4 5 1 2 "+" 5 7 2 2 "-" 7 9 2 2 "+" 9 10 2 1 "+" 10 12 1 2 "+" 12 15 2 1 "+" 15 16 1 1 "-" 16 17 1 1 "+" 17 18 1 2 "+" 18 19 2 1 "+" 19 20 1 2 "+"
Joshua Folorunso on 9 Nov 2022
Thank you very much. This is correct too.

Joshua Folorunso on 8 Dec 2022
I will.
It was a mistake while creating another question. I mistakenly edited old question.

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