Oops - yes you are quite right! The function integration-qag only returns two values, not three.
Thanks very much! -Alasdair On Sat, Oct 31, 2015 at 3:58 PM, Waldek Hebisch <hebi...@math.uni.wroc.pl> wrote: > Alasdair McAndrew wrote: > > > > I am enlarging Kurt and Bill's gsl.* function to include the gsl/gsll > > function integration-qag. This can be invoked, for example as > > > > )lisp (gsll:integration-qag (lambda (x) (exp (- (* x x)))) 0.0 1.0 > :gauss21) > > > > where the final :gauss21 is one of a number of parameters which define > the > > integration rule to be used. > > > > In my gsl.lisp file I have > > > > (defvar intrules (list ':gauss15 ':gauss21 ':gauss31 ':gauss41 ':gauss51 > > ':gauss61)) > > > > (defun integration-qag-list (f a b n) > > (multiple-value-list (integration-qag f a b (eval (nth n intrules))))) > > > > and in my corresponding gsl.spad: > > > > gslIntegrationQag(f,a,b,n) == > > r:List DF:=INTEGRATION_-QAG_-LIST(mkLispFunction1(f@ > > (DF->DF))$Lisp,a,b,n)$Lisp > > [r(1),r(2),r(3) pretend Integer] > > > > This all compiles OK. But in FriCAS: > > > > (1) -> gslIntegrationQag(x+->exp(-x^2),0.0,1.0,2) > > > > >> Error detected within library code: > > index out of range > > > > so clearly I've not set something up correctly - I suspect it's my > > cack-handed defvar list of parameters and my use of (nth n intrules). > But > > I don't know why this isn't working, and what I should be doing instead. > > Note that number 2 corresponds to :GAUSS31: > > )lisp (defvar intrules (list ':gauss15 ':gauss21 ':gauss31 ':gauss41 > ':ga)lisp (defvar intrules (list ':gauss15 ':gauss21 ':gauss31 ':gauss41 > ':gauss51 ':gauss61)) > > Value = INTRULES > (1) -> )lisp (nth 2 intrules) > > Value = :GAUSS31 > > AFAICS 'eval' in 'integration-qag-list' is not needed. But I do > not think this is reason for error. I would rather supect that > 'integration-qag' returns less values than you expect. Anyway > in such situation I would do > > )set break break > > run the offending command > > and then at Lisp debugger prompt (to avoid potentially too large > debugging printouts): > > (setf sb-ext:*debug-print-variable-alist* > '((*print-array* . nil) (*print-length* . 10))) > > Next: > > backtrace > > shows active calls and (if available) their arguments > > > -- > Waldek Hebisch > > -- > You received this message because you are subscribed to a topic in the > Google Groups "FriCAS - computer algebra system" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/fricas-devel/q18Av7P3jnM/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > fricas-devel+unsubscr...@googlegroups.com. > To post to this group, send email to fricas-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/fricas-devel. > For more options, visit https://groups.google.com/d/optout. > -- [image: http://www.facebook.com/alasdair.mcandrew] <http://www.facebook.com/alasdair.mcandrew> [image: https://plus.google.com/+AlasdairMcAndrew/posts] <https://plus.google.com/+AlasdairMcAndrew/posts> [image: https://www.linkedin.com/pub/alasdair-mcandrew/a/178/108] <https://www.linkedin.com/pub/alasdair-mcandrew/a/178/108> [image: https://twitter.com/amca01] <https://twitter.com/amca01> [image: http://numbersandshapes.net] <http://numbersandshapes.net> -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to fricas-devel+unsubscr...@googlegroups.com. To post to this group, send email to fricas-devel@googlegroups.com. Visit this group at http://groups.google.com/group/fricas-devel. For more options, visit https://groups.google.com/d/optout.
