one_dimension_evaluate.cpp

一维势阱计算基态能量本征值

#include<iostream.h>
#include<math.h>

double V=-5,W=1,Emin=-20,Emax=20,M=30,E,G1,G2,A,B,C,D,De,N,dwf1,dwf2,wf1,wf2,Test,nodes,Nlast;
char pan;

void wfcoef()
{
	G1=sqrt(fabs(V-E));
	G2=sqrt(fabs(E));
	wf1=1;
	dwf1=G2;
	A=G2/G1;
	B=1;
	wf2=A*sin(G1*W)+B*cos(G1*W);
	dwf2=G1*A*cos(G1*W)-B*G1*sin(G1*W);
	C=0.5*exp(-G2*W)*(wf2+dwf2/G2);
	D=0.5*exp(G2*W)*(wf2-dwf2/G2);
	return;
}

int main()
{
	cout<<'\t'<<'\t'<<"***********************************************"<<endl;
	cout<<'\t'<<'\t'<<"       一维势阱基态能量本征值计算软件"<<endl<<endl;
	cout<<'\t'<<'\t'<<"         预设精度0.0001         dss "<<endl;
	cout<<'\t'<<'\t'<<"***********************************************"<<endl;

aa:	cout<<endl<<"请依次输入 V，W，Emin，Emax，M 值 :"<<endl;
	cout<<"数据用空格或回车隔开,以回车结束，要求势阱深度V<0,宽度W>0,能量分割M>1且为整数"<<endl;
	cout<<"例如：-5 1 -20 20 30"<<endl<<endl;
	cin>>V>>W>>Emin>>Emax>>M;
bb:	if(M>1)
	{
		N=0;
		De=(Emax-Emin)/double(M-1);
		E=Emin-De;
		for(int i=0;i<M;i++)
		{
			E+=De;
			wfcoef();
			nodes=G1*W/3.1415926;
			Test=-C/D;
			if(Test>0)
				nodes++;
			if(!i)
				Nlast=nodes;
			else
				Nlast=N;
			N=nodes;
			cout<<E<<'\t'<<N<<endl;
			if(int(N)==1 && int(Nlast)==0)
			{
				if(De>=0.0001)
				{
					cout<<endl<<"缩小能量搜索范围及步长，提高精度再次迭代计算!"<<endl<<endl;
					Emin=E-De;
					Emax=E;
					goto bb;
				}
				else
				{
					cout<<endl<<endl<<"基态能量本征值为："<<E-De/2<<'\t'<<"误差："<<De<<endl<<endl;
					cout<<"计算结束，是否继续计算 y/n :";
					cin>>pan;
					if(pan=='y')
						goto aa;
					else
						return 0;
				}
			}
		}
	}
	else
	{
		cout<<endl<<"输入错误: M<=1"<<endl<<endl;
		goto aa;
	}
	cout<<endl;
	cout<<"##########################################################################"<<endl;
	cout<<"            对不起，未能找到基态能量本征值!"<<endl;
	cout<<"               请尝试扩大能量范围或增大M"<<endl;
	cout<<"##########################################################################"<<endl<<endl;
	goto aa;

}