detecting lisp overflow



>>>>> "Edwin" == Edwin Woollett <woollett at charter.net> writes:

    Edwin> I think the fog is clearing for me.
    Edwin> This is my first experience of dealing
    Edwin> with lisp print output which is not
    Edwin> a readable expression. Behind the
    Edwin> print output is a sensible lisp expression
    Edwin> which lisp functions can deal with,
    Edwin> and I am able to ask questions of the
    Edwin> list output of adaptive-plot.

    Edwin> The code is a work in progress.

    Edwin> -----------------------
    Edwin> (%i1) load("singular.lisp");
    Edwin> (%o1) "c:/work2/singular.lisp"
    Edwin> (%i2) singular(sin(x),[x,0,1]);
    Edwin> The value of R1 is (NIL NIL)
    Edwin> (%o2) done
    Edwin> (%i3) singular(exp(x),[x,1000,2000]);
    Edwin> overflow

    Edwin> The value of R1 is (T NIL)
    Edwin> (%o3) done
    Edwin> (%i4) singular(sin(x)/x,[x,-0.5,0.5]);
    Edwin> singular

    Edwin> The value of R1 is (NIL T)

Just wanted to let you know that adaptive-plot is not very precise
about when to return T.  I think basically any arithmetic-error causes
it to return T. 

I also suspect that singular(sin(x)/x, [x, -1, 0.5]) will not say it's
singular.

Ray