Flatten x0 and add guess for S0 as S(b=0)
Flatten x0 and add guess for S0 as S(b=0)

villalonreina/dipy,FrancoisRheaultUS/dipy,nilgoyyou/dipy,nilgoyyou/dipy,matthieudumont/dipy,FrancoisRheaultUS/dipy,villalonreina/dipy,matthieudumont/dipy