function r = ldivide(a, b)
% Quaternion left elementwise division is not implemented.
% This is because Matlab defines A ./ B to be the matrix with
% elements A(i, j)/B(i, j) and A .\ B to be the matrix with elements
% B(i, j)/A(i, j). This is not consistent with the ideas of left
% and right division in a non-commutative algebra, therefore it is
% not supported for quaternion arrays. The operator ./ implements
% elementwise division on the right, as expected, but to obtain
% elementwise division on the left use: inv(B) .* A

% Copyright © 2005 Stephen J. Sangwine and Nicolas Le Bihan.
% See the file : Copyright.m for further details.

help quaternion/ldivide;
error('Elementwise left division is not implemented for quaternions.');