/*計算正向差分以逼近雅克比行列式*/

#include?
#include?“nr.h“
using?namespace?std;

/*輸入x[0...n-1]是雅克比行列式被計算的點fvec[0...n-1]是在那點的函數值向量;
??vecfunc（xf）是用戶提供的程序它返回x點處的函數向量;
??輸出df[0...n-1][0...n-1]是雅克比矩陣*/

void?NR::fdjac（Vec_IO_DP?&x?Vec_I_DP?&fvec?Mat_O_DP?&dfvoid?vecfunc（Vec_I_DP?&?Vec_O_DP?&））
{
	const?DP?EPS=1.0e-8;???//逼近機器精度的平方根
	int?ij;
	DP?htemp;

	int?n=x.size（）;
	Vec_DP?f（n）;
	for?（j=0;j		temp=x[j];
		h=EPS*fabs（temp）;
		if?（h?==?0.0）?h=EPS;
		x[j]=temp+h;
		h=x[j]-temp;???????????//減小有限精度誤差的技巧
		vecfunc（xf）;
		x[j]=temp;
		for?（i=0;i			df[i][j]=（f[i]-fvec[i]）/h;
	}
}

?屬性????????????大小?????日期????時間???名稱
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?????文件????6876129??2013-05-03?11:30??two-point-problem\Ballistic.txt

?????文件??????17684??2013-05-02?18:22??two-point-problem\Debug\fdjac.obj

?????文件??????????0??2013-05-02?18:23??two-point-problem\Debug\fdjac.sbr

?????文件??????14488??2013-05-03?16:40??two-point-problem\Debug\fmin.obj

?????文件??????????0??2013-05-03?16:40??two-point-problem\Debug\fmin.sbr

?????文件??????64800??2013-05-02?18:25??two-point-problem\Debug\lnsrch.obj

?????文件??????????0??2013-05-02?18:25??two-point-problem\Debug\lnsrch.sbr

?????文件??????15449??2013-05-02?18:22??two-point-problem\Debug\lubksb.obj

?????文件??????????0??2013-05-02?18:23??two-point-problem\Debug\lubksb.sbr

?????文件??????64460??2013-05-02?18:22??two-point-problem\Debug\ludcmp.obj

?????文件??????????0??2013-05-02?18:23??two-point-problem\Debug\ludcmp.sbr

?????文件??????73476??2013-05-02?18:22??two-point-problem\Debug\newt.obj

?????文件??????????0??2013-05-02?18:23??two-point-problem\Debug\newt.sbr

?????文件??????66526??2013-05-03?16:39??two-point-problem\Debug\odeint.obj

?????文件??????????0??2013-05-03?16:39??two-point-problem\Debug\odeint.sbr

?????文件?????705536??2013-05-03?16:41??two-point-problem\Debug\opt_shoot.bsc

?????文件?????630883??2013-05-03?16:41??two-point-problem\Debug\opt_shoot.exe

?????文件?????934468??2013-05-03?16:41??two-point-problem\Debug\opt_shoot.ilk

?????文件????2820692??2013-05-03?16:41??two-point-problem\Debug\opt_shoot.pch

?????文件????1467392??2013-05-03?16:41??two-point-problem\Debug\opt_shoot.pdb

?????文件??????23819??2013-05-02?18:23??two-point-problem\Debug\rkck.obj

?????文件??????????0??2013-05-02?18:23??two-point-problem\Debug\rkck.sbr

?????文件??????64981??2013-05-03?09:20??two-point-problem\Debug\rkqs.obj

?????文件??????????0??2013-05-03?09:20??two-point-problem\Debug\rkqs.sbr

?????文件??????16105??2013-05-03?16:41??two-point-problem\Debug\shoot.obj

?????文件??????????0??2013-05-03?16:41??two-point-problem\Debug\shoot.sbr

?????文件?????258035??2013-05-03?16:41??two-point-problem\Debug\sphoot.obj

?????文件??????????0??2013-05-03?16:41??two-point-problem\Debug\sphoot.sbr

?????文件?????156672??2013-05-03?16:41??two-point-problem\Debug\vc60.idb

?????文件?????143360??2013-05-03?16:41??two-point-problem\Debug\vc60.pdb

............此處省略27個文件信息