How to avoid adding same elements

3 views (last 30 days)
MIch
MIch on 21 Sep 2022
Edited: Dyuman Joshi on 21 Sep 2022
Hello,
I have one question.
I need to sum elements of an matrix 1x7, but I need to exclude same elements.
For example
a=[5 4 3 2 1 1 6]
I would like to get b=5+4+3+2+1+6, not 5+4+3+2+1+1+6.

Accepted Answer

Dyuman Joshi
Dyuman Joshi on 21 Sep 2022
Edited: Dyuman Joshi on 21 Sep 2022
You can use unique to get the elements without repetition (subject to sum being less than 9007199254740992, as mentioned below)
%random data
a=[5 4 5 3 2 6 1 6 1 6];
b=unique(a,'stable')
b = 1×6
5 4 3 2 6 1
%using 'stable' to give an idea about the order
%you can use unique without 'stable' option as well
s=sum(b)
s = 21
Edit - In case you are dealing with fractional number, as @Walter Roberson commented,
sum(unique(a)) and sum(unique(a,'stable')) won't give the same answer.
  3 Comments
Dyuman Joshi
Dyuman Joshi on 21 Sep 2022
I am aware that one can use unique() without the 'stable' option, I just used stable option to give a hint.
Though you are right about fractions, I will edit my statement in my answer accordingly.
format long e
flintmax
ans =
9.007199254740992e+15
MIch
MIch on 21 Sep 2022
Thank you very much for your help.

Sign in to comment.

More Answers (0)

Categories

Find more on Mathematics in Help Center and File Exchange

Tags

Products

Community Treasure Hunt

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

Start Hunting!