I need to produce a matrix that has one's along the diagonal from the upper right to the lower left

77 views (last 30 days)
I need to produce a matrix along a square matrix of size "n" that has one's along the diagonal from the upper right to the lower left. I can't use "for" or an "if" statement. Any idea?
What doesn't work is:
function Y = reverse_diag(n)
zeroes = zero(n);
x = zero;
x(1:1:n,n:-1:1) =1;
Y = x;
end

Accepted Answer

DJ V
DJ V on 12 Nov 2016
Thanks, but use of diag is explicit;y forbidden.

More Answers (2)

Walter Roberson
Walter Roberson on 12 Nov 2016
n:n-1:something
  3 Comments

Sign in to comment.


Ahmet Cecen
Ahmet Cecen on 12 Nov 2016
x(1:1:n,n:-1:1) =1;
You cannot index points inside a matrix like that. MATLAB indexing reads like this:
Matrix(a,b) => For every a corresponding to every b.
So what you are doing is, say for the first row, fill every column (n:-1:1), then for the second row and so forth.
What you need to do is either use a for loop manually, or use the function:
diag()
followed by the function:
fliplr()

Categories

Find more on Creating and Concatenating Matrices in Help Center and File Exchange

Community Treasure Hunt

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

Start Hunting!

Translated by