* The condition for this is: * R' * R = I * and * det(R) =1 */ public boolean isRotationMatrix(matrix m) { double epsilon = 0.01; // margin to allow for rounding errors if (Math.abs(m[0][0]*m[0][1] + m[0][1]*m[1][1] + m[0][2]*m[1][2]) > epsilon) ...