add numerical recipes library

lib/nr/ansi/recipes/df1dim.c

@@ -0,0 +1,24 @@
+
+#define NRANSI
+#include "nrutil.h"
+
+extern int ncom;
+extern float *pcom,*xicom,(*nrfunc)(float []);
+extern void (*nrdfun)(float [], float []);
+
+float df1dim(float x)
+{
+	int j;
+	float df1=0.0;
+	float *xt,*df;
+
+	xt=vector(1,ncom);
+	df=vector(1,ncom);
+	for (j=1;j<=ncom;j++) xt[j]=pcom[j]+x*xicom[j];
+	(*nrdfun)(xt,df);
+	for (j=1;j<=ncom;j++) df1 += df[j]*xicom[j];
+	free_vector(df,1,ncom);
+	free_vector(xt,1,ncom);
+	return df1;
+}
+#undef NRANSI