ifg.for

有限元求解柏松方程。本文采用FORTRAN语言编制程序。程序中大部分变量采用有名公共区存储方式存储

      SUBROUTINE IFG !(N,M,II,XY)
	PARAMETER (PI=3.1415926)
	DOUBLE PRECISION HX,HY

	INTEGER N,M,NG,NP,ND,II(3,2*80*80),LEE,NS
	DOUBLE PRECISION XY(2,81*81)
	COMMON /C1/N,M,NP,ND/C2/NS,KD,NG,LEE
	COMMON /C6/XY,II 
	HX=PI/N
	HY=PI/M
	DO 10, J=1,M+1
	  DO 20, I=1,N+1
	    NG=(J-1)*(N+1)+I
	    XY(1,NG)=(I-1)*HX
	    XY(2,NG)=(J-1)*HY
   20   CONTINUE
   10 CONTINUE
	LE=0
	DO 30, J=1,M
	  NJ=(J-1)*(N+1)
	  DO 40, I=1,N
	    LE=LE+1
	    II(1,LE)=NJ+I
	    II(2,LE)=NJ+I+1
	    II(3,LE)=NJ+N+1+I
	    LE=LE+1
	    II(1,LE)=NJ+N+1+I+1
	    II(2,LE)=NJ+N+1+I
	    II(3,LE)=NJ+I+1
   40   CONTINUE
   30 CONTINUE
      print*,'LEE=',LEE
	END