Am Samstag, den 15.10.2011, 22:08 -0700 schrieb Raymond Toy:
> On 10/14/11 8:00 PM, Raymond Toy wrote:
> > Yes, definitely possible. I was lazy because qagp has one of the more
> > complicated interfaces. But I know more know about this kind of
> > interfacing than I did then.
> >
> > Could you add that as either feature request on maxima's bug tracker?
>
> Never mind.
>
> I've implemented the interface to qagp. You'll have to get to from git.
>
> A couple of examples:
>
> (%i17) quad_qags(abs(x-%pi/4)^(0.1),x,0,1);
> (%o17) [.8642219419275866, 1.701761398464896e-9, 945, 0]
> (%i18) quad_qagp(abs(x-%pi/4)^(0.1),x,0,1,[%pi/4]);
> (%o18) [.8642219426699342, 9.594790991384431e-16, 462, 0]
>
> Here, qagp is much more accurate and requires fewer evaluations.
>
> (%i19) quad_qags(abs(x-1/3)^(0.1),x,0,1);
> (%o19) [.8534810489167268, 9.475543115885799e-16, 189, 0]
> (%i20) quad_qagp(abs(x-1/3)^(0.1),x,0,1,[1/3]);
> (%o20) [.8534810489167265, 9.475543115885795e-16, 378, 0]
>
> In this case, the accuracy is comparable, but qags is less work.
>
> Finally,
>
> (%i21) quad_qags(x^3*log(abs((x^2-1)*(x^2-2))), x, 0, 3);
> (%o21) [52.74074847951494, 4.088443219529836e-7, 1869, 0]
> (%i22) quad_qagp(x^3*log(abs((x^2-1)*(x^2-2))), x, 0, 3, [1,sqrt(2)]);
> (%o22) [52.74074838347143, 2.6247632689546663e-7, 1029, 0]
>
> Here, qagp is more accurate and a bit less work.
Hello Ray,
when compiling quadpack.lisp I get an error with SBCL. The symbol j4save
is not exported. It works if I add the symbol j4save to the exported
symbols in the file slatec.lisp.
This is the message from the compiler:
; compiling (DEFUN QUAD_ARGUMENT_CHECK ...);
; compilation aborted because of fatal error:
; SB-INT:SIMPLE-READER-PACKAGE-ERROR at 10075 (line 328, column 17) on
#<SB-SYS:FD-STREAM
;
for "file /home/dieter/Maxima/maxima/src/numerical/slatec/quadpack.lisp"
;
{D022051}>:
; The symbol "J4SAVE" is not external in the SLATEC package.
Dieter Kaiser