Landweber iteration for nonnegative solutions [1, problem 6.2] Consider the following test problem from the regularization toolboz [A, xtrue]-phillips (n) xtrue = xtrue -0.5; % shift true sol by 0.5 xtrue(xtrue= 0 b-A+xtrue + 1e-1*randn (n, 1); % RHS + noise Solve this problem using both methods below with initial guess r0: . Method A: Regular Landweber iteration . Method B: Landweber iteration enforcing positivity where P : Rn Rn replaces all negative entries by zeroes. In Matlab you can achieve this with the inline function: P-(x) max (x,0) Landweber iteration for nonnegative solutions [1, problem 6.2] Consider the following test problem from the regularization toolboz [A, xtrue]-phillips (n) xtrue = xtrue -0.5; % shift true sol by 0.5 xtrue(xtrue= 0 b-A+xtrue + 1e-1*randn (n, 1); % RHS + noise Solve this problem using both methods below with initial guess r0: . Method A: Regular Landweber iteration . Method B: Landweber iteration enforcing positivity where P : Rn Rn replaces all negative entries by zeroes. In Matlab you can achieve this with the inline function: P-(x) max (x,0)