inter2.c

边界元程序

#include "cbox2.h"

void Inter2(F,Bc,Code,Xi,Yi,X,Y,u,q1,q2)	

float F[81],Bc[161],Xi[21],Yi[21],X[82],Y[82],u[21],q1[21],q2[21];
				int   Code[161];
	{
		float A1,B1,A2,B2,q11,q21,q12,q22,u11,u21,u12,u22,temp;
		int i,j,k;
		
		/*[ This Subroutine computes the values of the potential and the potential derivatives (fluxes) at the interior points ]*/ 
			
		/*[ Rearrange the F and Bc arrays to store all values of the potential in F and all valus of the derivative in Bc ]*/	
			
		for(i=1;i<=N;i++)
		{
			for(j=1;j<=2;j++)
			{
				if( Code[2*i - 2+j] <= 0)
				{
					if(!((i != N) || (j!=2)))
					{
						if(Code[1] >0)
						{
							temp       = F[1];
							F[1]    = Bc[2*N];
							Bc[2*N] = temp;
						}
						else
							Bc[2*N] = Bc[1];
					}
					else
					{
						if((i == 1) ||(j == 2)|| (Code[2*i -2] == 1))
						{
							temp 	= F[i-1+j];
							F[i-1+j] = Bc[2*i-2+j];
							Bc[2*i-2+j] = temp;
						}
						else
							Bc[2*i-1] = Bc[2*i-2];
					}
				}
			}
		}
			
		/*[ Compute the potential and fluxes at interior points ]*/
		
		if(L)
		{
			for(k=1;k<=L;k++)
			{
				u[k]   = 0.0;
				q1[k] = 0.0;
				q2[k] = 0.0;	
				for(j=1;j<=N;j++)
				{
					Quad2(Xi[k],Yi[k],X[j],Y[j],X[j+1],Y[j+1],
					&A1,&A2,&B1,&B2,&q11,&q21,&q12,&q22,
					&u11,&u21,&u12,&u22,1);
					
					if((j - N) < 0)
					{
						u[k]   += Bc[2*j-1]*B1 + Bc[2*j]*B2 - 
									F[j]*A1 - F[j+1]*A2;
						q1[k] += Bc[2*j-1]*u11+Bc[2*j]*u12-
									F[j]*q11-F[j+1]*q12;	
						q2[k] += Bc[2*j-1]*u21+Bc[2*j]*u22-
									F[j]*q21-F[j+1]*q22;
					}
					else
					{
						u[k]   += Bc[2*j-1]*B1+ Bc[2*j]*B2-F[j]
									*A1-F[1]*A2;
						q1[k] += Bc[2*j-1]*u11+Bc[2*j]*u12
									- F[j]*q11-F[1]*q12;
						q2[k] += Bc[2*j-1]*u21+Bc[2*j]*u22
									- F[j]*q21-F[1]*q22;
					}
				}
				u[k]   /= 2.0 * pi;
				q1[k] /= 2.0 * pi;
				q2[k] /= 2.0 * pi;  
		 	}
		} 
	}