| 
 
	积分123贡献 精华在线时间 小时注册时间2012-8-16最后登录1970-1-1 
 | 
 
| 
C==================== *SUB JACOBI*===========================
x
登录后查看更多精彩内容~您需要 登录 才可以下载或查看,没有帐号?立即注册 
  SUBROUTINE JACOBI(N,A,D,V,EVL,B,Z)
 DIMENSION A(N,N),D(N),V(N,N),B(N),Z(N)
 LOGICAL EVL
 IF(.NOT.EVL) GO TO 10
 DO 70 IP=1,N
 DO 70 IQ=1,N
 IF (IP-IQ) 50,60,50
 60  V(IP,IP)=1.0
 GO TO 70
 50  V(IP,IQ)=0.0
 70  CONTINUE
 10  DO 80 IP=1,N
 D(IP)=A(IP,IP)
 B(IP)=D(IP)
 80  Z(IP)=0.0
 IROT=0
 DO 370 I=1,50
 SM=0.0
 NM1=N-1
 DO 100 IP=1,NM1
 IPP1=IP-1
 DO 100 IQ=IPP1,N
 100  SM=SM+ABS(A(IP,IQ))
 IF (SM) 110,120,110
 110  IF (I-4) 130,140,140
 130  TRESH=0.2*SM/(FLOAT(N)*FLOAT(N))
 GO TO 150
 140  TRESH=0.0
 150  DO 160 IP=1,NM1
 IPP1=IP+1
 DO 160 IQ=IPP1,N
 G=100.0*ABS(A(IP,IQ))
 IF(I.GT.4.AND.ABS(D(IP))+G.EQ.ABS(D(IP)).AND.ABS(D(IQ))+G.EQ.
 *ABS(D(IQ))) GO TO 200
 IF(ABS(A(IP,IQ)).LE.TRESH) GO TO 160
 H=D(IQ)-D(IP)
 IF(ABS(H)+G.EQ.ABS(H)) GO TO 240
 THETA=0.5*H/A(IP,IQ)
 T=1.0/(ABS(THETA)+SQRT(1.0+THETA*THETA))
 IF(THETA.LT.0.0) T=-T
 GO TO 250
 240  T=A(IP,IQ)/H
 250  C=1.0/SQRT(1.0+T*T)
 S=T*C
 H=T*A(IP,IQ)
 Z(IP)=Z(IP)-H
 Z(IQ)=Z(IQ)+H
 D(IP)=D(IP)-H
 D(IQ)=D(IQ)+H
 A(IP,IQ)=0.0
 IPM1=IP-1
 IF (IPM1) 260,260,270
 270  DO 280 J=1,IPM1
 G=A(J,IP)
 H=A(J,IQ)
 A(J,IP)=C*G-S*H
 280  A(J,IQ)=S*G+C*H
 260  IQM1=IQ-1
 IF (IQM1-IPP1) 300,290,290
 290  DO 310 J=IPP1,IQM1
 G=A(IP,J)
 H=A(J,IQ)
 A(IP,J)=C*G-S*H
 310  A(J,IQ)=S*G+C*H
 300  IQP1=IQ+1
 IF (N-IQP1) 330,320,320
 320  DO 340 J=IQP1,N
 G=A(IP,J)
 H=A(IQ,J)
 A(IP,J)=C*G-S*H
 340  A(IQ,J)=S*G+C*H
 330  IF  (.NOT.EVL) GO TO 350
 DO 360 J=1,N
 G=V(J,IP)
 H=V(J,IQ)
 V(J,IP)=C*G-S*H
 360  V(J,IQ)=S*G+C*H
 350  IROT=IROT+1
 GO TO 160
 200  A(IP,IQ)=0.0
 160  CONTINUE
 DO 370 IP=1,N
 B(IP)=B(IP)+Z(IP)
 D(IP)=B(IP)
 370  Z(IP)=0.0
 120   RETURN
 END
 | 
 |