23 lines
323 B
C++
23 lines
323 B
C++
#include "nr.h"
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void NR::locate(Vec_I_DP &xx, const DP x, int &j)
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{
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int ju,jm,jl;
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bool ascnd;
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int n=xx.size();
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jl=-1;
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ju=n;
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ascnd=(xx[n-1] >= xx[0]);
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while (ju-jl > 1) {
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jm=(ju+jl) >> 1;
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if (x >= xx[jm] == ascnd)
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jl=jm;
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else
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ju=jm;
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}
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if (x == xx[0]) j=0;
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else if (x == xx[n-1]) j=n-2;
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else j=jl;
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}
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