add numerical recipes library

lib/nr/k_and_r/recipes/amotsa.c

@@ -0,0 +1,37 @@
+
+#include <math.h>
+#include "nrutil.h"
+
+extern long idum;
+extern float tt;
+
+float amotsa(p,y,psum,ndim,pb,yb,funk,ihi,yhi,fac)
+float (*funk)(),**p,*yb,*yhi,fac,pb[],psum[],y[];
+int ihi,ndim;
+{
+	float ran1();
+	int j;
+	float fac1,fac2,yflu,ytry,*ptry;
+
+	ptry=vector(1,ndim);
+	fac1=(1.0-fac)/ndim;
+	fac2=fac1-fac;
+	for (j=1;j<=ndim;j++)
+		ptry[j]=psum[j]*fac1-p[ihi][j]*fac2;
+	ytry=(*funk)(ptry);
+	if (ytry <= *yb) {
+		for (j=1;j<=ndim;j++) pb[j]=ptry[j];
+		*yb=ytry;
+	}
+	yflu=ytry-tt*log(ran1(&idum));
+	if (yflu < *yhi) {
+		y[ihi]=ytry;
+		*yhi=yflu;
+		for (j=1;j<=ndim;j++) {
+			psum[j] += ptry[j]-p[ihi][j];
+			p[ihi][j]=ptry[j];
+		}
+	}
+	free_vector(ptry,1,ndim);
+	return yflu;
+}