matlab - Unable to perform assignment because the size of the left side is 1-by-7-by-7 and the size of the right side is 6-by-6

Question

Closed. This question needs debugging details. It is not currently accepting answers. question from:https://stackoverflow.com/questions/65907134/unable-to-perform-assignment-because-the-size-of-the-left-side-is-1-by-7-by-7-an

Answer 1

From the documentation for eigs:

d = eigs(A) returns a vector of the six largest magnitude eigenvalues of matrix A.

If you want all seven, you need to call d = eigs(A,7) or d = eig(A). For a small matrix (e.g. < 1000 x 1000) it's usually easier to just get all the eigenvalues with eig, rather than get a subset with eigs.

Edit: Responding to your "Update 3"

for k=1:length(D) should be replaced by for k=1:n. This needs to be changed on two lines. Judging from your error message they are lines 231 and 236.

L = length(X) returns the length of the largest array dimension in X, which in your case is 7, i.e. too high for the first dimension.