how can I speed up bromberg?



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

    Edwin> On Nov. 20, 2012, Raymond Toy wrote:
    Edwin> ----------------------------------------------
    Edwin> I am getting a Lisp error message when I use your version:
    >>> 
    >> Oops. I've uploaded a new version that fixes this.
    >> 
    >> Unfortunately, it still takes a very long time.  My original test used
    >> the default parameters and it converged very quickly.  With your new
    >> parameters, I gave up after a minute or so.
    >> 
    >> But I think the problem is with the integrand, 1/(1+sqrt(x)).  I'm
    >> guessing the infinite slope at 0 is going to give lots of trouble.
    >> bromberg(g, 1/2, 1) returns instantly. bromberg(g,1/100,1) takes a
    >> little bit longer.
    >> 
    >> Don't know if this will help or not, but it might be worthwhile to
    >> implement tanh-sinh quadrature
    >> (http://en.wikipedia.org/wiki/Tanh-sinh_quadrature).  (I think Richard
    >> has mentioned this before.)
    Edwin> ------------------------------------------------
    Edwin> I haven't tried your newest version of bromberg.lisp yet.

    Edwin> However in reference to your last remarks, I would like to emphasize
    Edwin> that the famous tanh-sinh quadrature method has been
    Edwin> available to Maxima users for a "long time".

Oh, I didn't know that.  Given that, is there any real reason to have
bromberg?

Ray