how I can eliminate in a matrix all columns whose last two elements are equal? in Matlab
A=[1 2 3 ; 4 5 6 ; 5 5 5]

A =

     1     2     3
     4     5     6
     5     5     5

A(:,A(end,:)==A(end-1,:))=[]

A =

     1     3
     4     6
     5     5

index = (A(:,end) == A(:,end-1) );

A(:,index) = [];

B = A( : , A(: , end-1) ~= A(: , end) )