[SciPy-dev] iterative callback function signature

Hi, I'm trying to monitor the residual while doing an iterative solve. In iterative.py I see: x, iter_, resid, info, ndx1, ndx2, sclr1, sclr2, ijob = \ revcom(b, x, work, iter_, resid, info, ndx1, ndx2, ijob) if callback is not None and iter_ > olditer: callback(x) I'm a bit uneducated about the meaning of all the iterative variables, but is there a way I can obtain the residual from x here? Otherwise, would it not make sense to allow more complicated callback functions? Thanks Neilen