building fft

otlore dolire
 Jonathan Roewen
 Shawn
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Date:  20060602 (11:21) 
From:  Jonathan Roewen <jonathan.roewen@g...> 
Subject:  Re: [Camllist] building fft 
variables have to start with a lowercase letter. values starting with uppercase are module names/type constructors. On 6/2/06, otlore dolire <otlore@hotmail.fr> wrote: > I have a problem with a basic fft function i'm tryin to build. I think it's > right, yet it raises conflicts, as if it didn't recognize the "end" at the > end of it. Can you please tell me if someone sees something wrong? thx in > advance > > let rec fft N w y = > let Y = make_vect N {Re = 0. ; Im = 0.} > in > if N = 1 then begin Y.(0) < y.(0) end > else > begin let m = div_int N 2; > let l1 = make_vect m {Re = 0. ; Im = 0. } > and l2 = make_vect m {Re = 0. ; Im = 0. } > in for k = 0 to m  1 do > l1.(k) < y.(2*k); > l2.(k) < y.(2*k + 1) > done; > let L1 = make_vect m {Re = 0. ; Im = 0. } > and L2 = make_vect m {Re = 0. ; Im = 0. } > in > for i = 0 to m  1 do > L1.(i) < (fft m (prod w w) l1).(i); > L2.(i) < (fft m (prod w w) l2).(i) > done; > let wk = ref {Re = 1. ; Im = 0. } > and P = ref {Re = 0. ; Im = 0. } > and I = ref {Re = 0. ; Im = 0. } > in for k=0 to m  1 do > P := L1.(k); > I := prod !wk L2.(k); > Y.(k) < prod (add !P !I) {Re = 0.5 ; Im = 0. }; > Y.(k + m) < prod (sous !P !I) {Re = 0.5 ; Im = 0. }; > wk := prod !wk w > done > end; > Y;; > > > PS: i defined the type cplx by type cplx = {Re : float ; Im : float}, prod, > add and sous are respectively product, addition and substraction of cplx > numbers > > _________________________________________________________________ > Windows Live Mail : découvrez et testez la version bêta ! > http://www.ideas.live.com/programpage.aspx?versionId=5d21c51ab16143149b0e4911fb2b2e6d > > _______________________________________________ > Camllist mailing list. Subscription management: > http://yquem.inria.fr/cgibin/mailman/listinfo/camllist > Archives: http://caml.inria.fr > Beginner's list: http://groups.yahoo.com/group/ocaml_beginners > Bug reports: http://caml.inria.fr/bin/camlbugs >