Actually, I'm mystified about the meaning of iter_ in gmres() and the others. Can anyone shed any light on this? Why is the output value of iter_ from revcom() used as the *input* value in the next iteration? Why is the maxiter argument only used once, for the first call to revcom(), and then apparently ignored for all subsequent calls?
I'm inclined to revert the callback patch -- it seems broken. But if the revcom Fortran functions can perform multiple iterations each, we can't easily call back Python functions each iteration. Is there a better solution?
-- Ed