add numerical recipes library

lib/nr/cpp/recipes/anneal.cpp

@@ -0,0 +1,77 @@
+#include <iostream>
+#include <iomanip>
+#include <cmath>
+#include <cstdlib>
+#include "nr.h"
+using namespace std;
+
+namespace {
+	inline DP alen(const DP a, const DP b, const DP c, const DP d)
+	{
+		return sqrt((b-a)*(b-a)+(d-c)*(d-c));
+	}
+}
+
+void NR::anneal(Vec_I_DP &x, Vec_I_DP &y, Vec_IO_INT &iorder)
+{
+	const DP TFACTR=0.9;
+	bool ans;
+	int i,i1,i2,idec,idum,j,k,nn,nover,nlimit,nsucc;
+	static Vec_INT n(6);
+	unsigned long iseed;
+	DP path,de,t;
+
+	int ncity=x.size();
+	nover=100*ncity;
+	nlimit=10*ncity;
+	path=0.0;
+	t=0.5;
+	for (i=0;i<ncity-1;i++) {
+		i1=iorder[i];
+		i2=iorder[i+1];
+		path += alen(x[i1],x[i2],y[i1],y[i2]);
+	}
+	i1=iorder[ncity-1];
+	i2=iorder[0];
+	path += alen(x[i1],x[i2],y[i1],y[i2]);
+	idum = -1;
+	iseed=111;
+	cout << fixed << setprecision(6);
+	for (j=0;j<100;j++) {
+		nsucc=0;
+		for (k=0;k<nover;k++) {
+			do {
+				n[0]=int(ncity*ran3(idum));
+				n[1]=int((ncity-1)*ran3(idum));
+				if (n[1] >= n[0]) ++n[1];
+				nn=(n[0]-n[1]+ncity-1) % ncity;
+			} while (nn<2);
+			idec=irbit1(iseed);
+			if (idec == 0) {
+				n[2]=n[1]+int(abs(nn-1)*ran3(idum))+1;
+				n[2] %= ncity;
+				de=trncst(x,y,iorder,n);
+				ans=metrop(de,t);
+				if (ans) {
+					++nsucc;
+					path += de;
+					trnspt(iorder,n);
+				}
+			} else {
+				de=revcst(x,y,iorder,n);
+				ans=metrop(de,t);
+				if (ans) {
+					++nsucc;
+					path += de;
+					reverse(iorder,n);
+				}
+			}
+			if (nsucc >= nlimit) break;
+		}
+		cout << endl << "T = " << setw(12) << t;
+		cout << "	 Path Length = " << setw(12) << path << endl;
+		cout << "Successful Moves: " << nsucc << endl;
+		t *= TFACTR;
+		if (nsucc == 0) return;
+	}
+}