Algorithm 1: Nonnegative Orthogonal Matching Pursuit
Input: signal y, Dictionary A, sparsity n, x = 0
Output: signal weights x
1: initialize r0 = y, s = ∅, i = 0
2: while i < n & max(Atri) > 0 do
3: k = argmax(Atri)
4: s = s U k
5: xs = argminθ>0 ||y ‐ Asθ||2
6: ri+1 = y ‐ Asxs
7: i = i + 1
8: End while
9: x(s) = xs