29 lines
484 B
C++
29 lines
484 B
C++
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#ifndef _COSMOTOOL_NEWTON_HPP
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#define _COSMOTOOL_NEWTON_HPP
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namespace CosmoTool
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{
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template<typename T, typename FunT>
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T newtonSolver(T x0, FunT function, double residual = 1e-3)
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{
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T x, xold = x0;
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T f_x = function.eval(x0);
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T df_x = function.derivative(x0);
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x = xold - f_x/df_x;
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while (abs(xold-x) > residual)
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{
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xold = x;
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f_x = function.eval(x);
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df_x = function.derivative(x);
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x = xold - f_x/df_x;
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}
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return x;
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}
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};
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#endif
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