Element by Element Subtraction

128 vues (au cours des 30 derniers jours)
Sanim Rahman
Sanim Rahman le 10 Déc 2017
Commenté : anuforo peter le 7 Mar 2020
I am trying to do element by element subtraction like the following:
a= [1,2,3,4,5] b= [-1,-2,-3]
I would like my output to be "a" to be subtracted by the first element of "b" then by the second element and so on. The output "c" should look like: c=[2,3,4,5,6,3,4,5,6,7...]
I understand that if I simply do "c=a-b" will not work because the dimensions do not agree. Would something like this require a loop?

Réponse acceptée

Image Analyst
Image Analyst le 10 Déc 2017
Try this:
a= [1,2,3,4,5]
b= [-1,-2,-3]
c = a' - b;
c = c(:)'
You get
c =
2 3 4 5 6 3 4 5 6 7 4 5 6 7 8
in R2016b (I believe) or later that has automatic expansion capability.
  3 commentaires
anuforo peter
anuforo peter le 7 Mar 2020
What about doing this on a mutidimensional array
anuforo peter
anuforo peter le 7 Mar 2020
Please help! Thank you ?

Connectez-vous pour commenter.

Plus de réponses (1)

Kaushik Lakshminarasimhan
Kaushik Lakshminarasimhan le 10 Déc 2017
minus operator in Matlab can inherently handle this, so you don't need a loop. Checkout >> help minus. For your case, something like this will work.
a= [1,2,3,4,5]; b= [-1,-2,-3];
c = reshape(a'-b,1,numel(a)*numel(b));

Catégories

En savoir plus sur Loops and Conditional Statements dans Help Center et File Exchange

Community Treasure Hunt

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

Start Hunting!

Translated by