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building fft
• otlore dolire
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 Date: -- (:) From: otlore dolire Subject: building fft
```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

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,