Last change
on this file since 341 was
231,
checked in by lmdzadmin, 23 years ago
|
Merge avec la branche principale
LF
|
-
Property svn:eol-style set to
native
-
Property svn:executable set to
*
-
Property svn:keywords set to
Author Date Id Revision
|
File size:
2.5 KB
|
Rev | Line | |
---|
[2] | 1 | SUBROUTINE JACOBI(A,N,NP,D,V,NROT) |
---|
[231] | 2 | PARAMETER (NMAX=400) |
---|
[2] | 3 | DIMENSION A(NP,NP),D(NP),V(NP,NP),B(NMAX),Z(NMAX) |
---|
| 4 | IF (n.gt.nmax) THEN |
---|
| 5 | print*, 'n, nmax=', n, nmax |
---|
| 6 | print*, 'Surdimensionnement insuffisant dans jacobi' |
---|
| 7 | CALL abort |
---|
| 8 | ENDIF |
---|
| 9 | DO 12 IP=1,N |
---|
| 10 | DO 11 IQ=1,N |
---|
| 11 | V(IP,IQ)=0. |
---|
| 12 | 11 CONTINUE |
---|
| 13 | V(IP,IP)=1. |
---|
| 14 | 12 CONTINUE |
---|
| 15 | DO 13 IP=1,N |
---|
| 16 | B(IP)=A(IP,IP) |
---|
| 17 | D(IP)=B(IP) |
---|
| 18 | Z(IP)=0. |
---|
| 19 | 13 CONTINUE |
---|
| 20 | NROT=0 |
---|
| 21 | DO 24 I=1,50 |
---|
| 22 | SM=0. |
---|
| 23 | DO 15 IP=1,N-1 |
---|
| 24 | DO 14 IQ=IP+1,N |
---|
| 25 | SM=SM+ABS(A(IP,IQ)) |
---|
| 26 | 14 CONTINUE |
---|
| 27 | 15 CONTINUE |
---|
| 28 | IF(SM.EQ.0.)RETURN |
---|
| 29 | IF(I.LT.4)THEN |
---|
| 30 | TRESH=0.2*SM/N**2 |
---|
| 31 | ELSE |
---|
| 32 | TRESH=0. |
---|
| 33 | ENDIF |
---|
| 34 | DO 22 IP=1,N-1 |
---|
| 35 | DO 21 IQ=IP+1,N |
---|
| 36 | G=100.*ABS(A(IP,IQ)) |
---|
| 37 | IF((I.GT.4).AND.(ABS(D(IP))+G.EQ.ABS(D(IP))) |
---|
| 38 | * .AND.(ABS(D(IQ))+G.EQ.ABS(D(IQ))))THEN |
---|
| 39 | A(IP,IQ)=0. |
---|
| 40 | ELSE IF(ABS(A(IP,IQ)).GT.TRESH)THEN |
---|
| 41 | H=D(IQ)-D(IP) |
---|
| 42 | IF(ABS(H)+G.EQ.ABS(H))THEN |
---|
| 43 | T=A(IP,IQ)/H |
---|
| 44 | ELSE |
---|
| 45 | THETA=0.5*H/A(IP,IQ) |
---|
| 46 | T=1./(ABS(THETA)+SQRT(1.+THETA**2)) |
---|
| 47 | IF(THETA.LT.0.)T=-T |
---|
| 48 | ENDIF |
---|
| 49 | C=1./SQRT(1+T**2) |
---|
| 50 | S=T*C |
---|
| 51 | TAU=S/(1.+C) |
---|
| 52 | H=T*A(IP,IQ) |
---|
| 53 | Z(IP)=Z(IP)-H |
---|
| 54 | Z(IQ)=Z(IQ)+H |
---|
| 55 | D(IP)=D(IP)-H |
---|
| 56 | D(IQ)=D(IQ)+H |
---|
| 57 | A(IP,IQ)=0. |
---|
| 58 | DO 16 J=1,IP-1 |
---|
| 59 | G=A(J,IP) |
---|
| 60 | H=A(J,IQ) |
---|
| 61 | A(J,IP)=G-S*(H+G*TAU) |
---|
| 62 | A(J,IQ)=H+S*(G-H*TAU) |
---|
| 63 | 16 CONTINUE |
---|
| 64 | DO 17 J=IP+1,IQ-1 |
---|
| 65 | G=A(IP,J) |
---|
| 66 | H=A(J,IQ) |
---|
| 67 | A(IP,J)=G-S*(H+G*TAU) |
---|
| 68 | A(J,IQ)=H+S*(G-H*TAU) |
---|
| 69 | 17 CONTINUE |
---|
| 70 | DO 18 J=IQ+1,N |
---|
| 71 | G=A(IP,J) |
---|
| 72 | H=A(IQ,J) |
---|
| 73 | A(IP,J)=G-S*(H+G*TAU) |
---|
| 74 | A(IQ,J)=H+S*(G-H*TAU) |
---|
| 75 | 18 CONTINUE |
---|
| 76 | DO 19 J=1,N |
---|
| 77 | G=V(J,IP) |
---|
| 78 | H=V(J,IQ) |
---|
| 79 | V(J,IP)=G-S*(H+G*TAU) |
---|
| 80 | V(J,IQ)=H+S*(G-H*TAU) |
---|
| 81 | 19 CONTINUE |
---|
| 82 | NROT=NROT+1 |
---|
| 83 | ENDIF |
---|
| 84 | 21 CONTINUE |
---|
| 85 | 22 CONTINUE |
---|
| 86 | DO 23 IP=1,N |
---|
| 87 | B(IP)=B(IP)+Z(IP) |
---|
| 88 | D(IP)=B(IP) |
---|
| 89 | Z(IP)=0. |
---|
| 90 | 23 CONTINUE |
---|
| 91 | 24 CONTINUE |
---|
| 92 | STOP '50 iterations should never happen' |
---|
| 93 | RETURN |
---|
| 94 | END |
---|
Note: See
TracBrowser
for help on using the repository browser.