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AnopT
03/24/09 02:34am

Hello. I have a code of golden section method. Why it is performed so slowly (more than 10 minutes)?

f[x_] := x^2 - Sin[x]*Cos[x];
(*заданные значения*)
dx0 = 0.1;
dy0 = 0.01;
a0 = -10;
b0 = 100;
g = GoldenRatio - 1;
i = 0;
(*реализация алгоритма*)
GoldSearch[f0_, a0_, b0_, dx0_, dy0_] :=
Module[{a = a0, b = b0, dx = dx0, dy = dy0},
While[dx >= dx0, l1 = g*(Abs[a] + Abs[b]);
x1 = l1;
x2 = (Abs[a] + Abs[b])/2 - l1;
If[f[x1] > f[x2], {a = x1, b = x2}];
If[f[x1] < f[x2], {a = x2, b = x1}];
Print[N[a] " ", N[f[x1]], " ", N[b], " ", N[f[x2]]];
dx = Abs[a] + Abs[b];
i++;
(*Print[N[x1]," ",N[x2]];*)
]; {N[a], N[f[(a + b)/2]]}];
GoldSearch[f[x], a0, b0, 0.1, 1]
min = FindMinimum[f[x], {x, 5}];
Print["Минимум функции ", f[x], " лежит в точке ", min];
Plot[f[x], {x, -50, 50}]



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Subject (listing for 'so slowly')
Author Date Posted
so slowly AnopT 03/24/09 02:34am
Re: so slowly yehuda ben-s... 03/29/09 11:38am
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