On 10/16/11 7:40 AM, Dieter Kaiser wrote:
> 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.
>
That's because I was stupid and forgot to check in my changes and push
it to the repo.
Ray