"jelle" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > >You could probably write your own FixedPoint function without too much >>difficulty, with the only tricky part being for it to know when to > stop! > > It would be quite interesting to have this kind of function. But > likely its far from trivial.
Fixed point iteration is a standard technique in numerical analysis -- floating point calculations as approximation of real-number functions. The first problem is getting an equation form that will converge -- which has a stable, preferably unique fixed point. The second is how to start -- getting a first approximation that leads to convergence. For stopping, one must choose between relative and absolute changes in the variable or expression (in x or y) or some combiniation thereof. > FixedPoint seems to be one of the core functions in Mathematica, where > many other functions are based on. Some additions such as FixedPoint > would make functional programming in Python [easier]. It belongs in a module of floating-point equation solvers. Perhaps one is already in scipy. Terry J. Reedy -- http://mail.python.org/mailman/listinfo/python-list
