🚀 go-pugleaf

In article <1926@hsdndev.UUCP> stvjc@gauss.med.harvard.edu (Vincent Carey 2-3265) writes:
>would appreciate references or pointers on software for
>function plotting in which grid points are chosen more
>finely as the function becomes rougher.

There was a paper by Richard Fateman (of UC Berkeley) titled 
"Honest Plotting, Global Extrema, and Interval Arithmetic".

I ftp'ed it from <I-dont-remember-where> and I don't have
a copy online anymore. Here's the abstract

____
        A computer program to honestly plot curves y = f(x) must
     locate maxima and minima in the domain of the graph. To
     do so it may have to solve a classic problem in computation -
     global optimization. Reducing an easy problem to a hard one
     is usually not an advantage, but in fact there is a route to
     solving both problems if the function can be evaluated using
     interval arithmetic. Since some computer algebra systems
     supply a version of interval arithmetic, it seems we have the
     ingredients for a solution.
        In this paper we address a particular problem how to compute
     display "honest" graphs of 2-D mathematical curves. By "honest"
     we mean that no significant features (such as the location of
     poles, the values at maxima or minima, or the behaviour of a
     curve at asymptotes) are misrepresented. By "mathematical" we mean
     curves like those generally needed in scientific disciplines
     where functions are represented by composition of common
     mathematical operations: rational operations (+, -, *, /),
     exponential and log, trigonometric functions as well as
     continuous and differentiable functions from applied mathematics.
____

I also don't know where it was published. You may be able to contact
the author at "fateman@math.berkeley.edu".

--
Taj Khattra