Brilliant! - thank you so much - that works just as it should. Why cannot the input to integration-qagp be simply a list or a vector? As in (gsll:integration-QAGp 'integration-test-f454 '(0.0d0 1.0d0 (sqrt 2.0d0) 3.0d0) 0.0d0 1.0d-3 1000) or (gsll:integration-QAGp 'integration-test-f454 (vector 0.0d0 1.0d0 (sqrt 2.0d0) 3.0d0) 0.0d0 1.0d-3 1000) I'm not sure (told you I was a newbie!) what grid provides that a list or vector can't. And here's a tiny problem from my tiny brain: suppose the endpoints and singularities are given as a standard Lisp list, S say. Then (I'm using SBCL): (defvar S2) (setf S2 (grid:make-foreign-array 'double-float :dimensions (length S) :initial-contents S)) turns the list into a foreign array grid (is there an easier way?). But then, my attempts to use S2 as input to gaqp produces errors: (gsll:integration-QAGp 'my-fun 'S2 0.0d0 1.0d-3 1000) Basically I need a way of turning a numeric list into input for integration-QAGp. I'll keep fiddling! Many thanks again, Alasdair On Mon, Nov 2, 2015 at 1:34 PM, Liam Healy <lhealy@common-lisp.net> wrote:
On Sun, Nov 1, 2015 at 5:10 AM, Alasdair McAndrew <amca01@gmail.com> wrote:
Hello,
I am using the excellent gsll package (in the first instance), to provide an interface to quadpack for the mathematics system FriCAS. I'm slowly going through calculus/numerical-integration.lisp one function at a time and writing each one into FriCAS as I go. This means writing functions in FriCAS's own language SPAD which interface with gsll.
This is made harder by me being a lisp newbie.
However, I've come to integration-QAGP, and I've tried to run the test command (having first defined the function it calls). However, all I get is errors.
I'm using SBCL in emacs-slime, and I have installed gsll with quicklisp, so that I can call an integration routine with
* (gsll:integration-qng (lambda (x) (exp (- (* x x)))) 0.0 1.0)
But the commands
* (defun integration-test-f454 (x) (* (expt x 3) (* (log (abs (* (- (expt x 2) 1.0d0) (- (expt x 2) 2.0d0)))))))
* (gsll:integration-QAGp 'integration-test-f454 (grid:copy-to (vector 0.0d0 1.0d0 (sqrt 2.0d0) 3.0d0)) 0.0d0 1.0d-3 1000)
just produces a long list of errors. Is "grid" a standard library, or does it need to be loaded first? (Told you I was a newbie...)
Thanks Alasdair --
Try this
(setf grid:*default-grid-type* 'grid:foreign-array) (gsll:integration-QAGp 'integration-test-f454 (grid:grid 0.0d0 1.0d0 (sqrt 2.0d0) 3.0d0) 0.0d0 1.0d-3 1000)
and let us know what happens.
Thanks, Liam
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