On Thu, Sep 25, 2008 at 2:40 PM, Edwin Woollett <woollett at charter.net> wrote:
> I get quad_qag(..) error message no. 2
> ("excessive roundoff error") with
> a very simple function f(x) = x.
The exact result is 0 which makes the relative error calculation undefined.
(I don't remember quadpack's definition of relative error offhand.)
I'm pretty sure if you tried f(x) := x over different ranges,
the error would go away.
> 2. Why are the SLATEC error messages
> progressively disappearing the more
> times we call quad_qags(..) with
> the same function? ("message exhaustion")
Maybe there is some logic to suppress repeated message.
Dunno for sure; I 'd have to look at the code.
Robert Dodier