Hi, I have found two aproximations x1 and x2 to the solution of a linear system A*x=b by two different methods with the same relative residual "e". That is |A*x1 - b| < e*|b| and |A*x2 - b| < e*|b|. For debugging purposes I want to know if an upper bound for |x1 - x2| can be derived from the two inequalities above. I have gone this far in trying to find it:
From the triangle inequality |A*x1 - b -(A*x2 - b)| <= |A*x1 - b| + |A*x2 - b| = 2*e*|b|, eliminating the b's in the left hand side, |A*(x1-x2)| <= 2*e*|b|, Does anybody know if from here a condition of the form |x1-x2| <= ? can be derived? Thanks -- Alejandro
